Eliminate redundant getFhirClientForR4() calls in location pagination

[Copilot]

Addresses #129 (comment)

Description

The collectAllLocations method called getFhirClientForR4() three times per pagination iteration: once for instanceof check, once for cast, and once for loadPage(). Stored result in local variable to eliminate redundant calls.

Before:

if (getFhirClientForR4() instanceof GenericClient) {
    Utils.cleanUpBundlePaginationNextLinkServerBaseUrl(
            (GenericClient) getFhirClientForR4(), currentPage);
}

try {
    currentPage = getFhirClientForR4().loadPage().next(currentPage).execute();
}

After:

IGenericClient fhirClient = getFhirClientForR4();
if (fhirClient instanceof GenericClient) {
    Utils.cleanUpBundlePaginationNextLinkServerBaseUrl(
            (GenericClient) fhirClient, currentPage);
}

try {
    currentPage = fhirClient.loadPage().next(currentPage).execute();
}

Engineer Checklist

• I have written Unit tests for any new feature(s) and edge cases for
  bug fixes
• I have added documentation for any new feature(s) and configuration
  option(s) on the README.md
• I have run mvn spotless:check to check my code follows the project's
  style guide
• I have run mvn clean test jacoco:report to confirm the coverage report
  was generated at plugins/target/site/jacoco/index.html
• I ran mvn clean package right before creating this pull request.

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[Copilot]

Just as a heads up, I was blocked by some firewall rules while working on your feedback. Expand below for details.

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• central.sonatype.com
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/fhir-gateway-extension/fhir-gateway-extension org.codehaus.plexus.classworlds.launcher.Launcher clean compile -DskipTests (dns block)
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/fhir-gateway-extension/fhir-gateway-extension/plugins org.codehaus.plexus.classworlds.launcher.Launcher clean compile -DskipTests (dns block)
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/fhir-gateway-extension/fhir-gateway-extension org.codehaus.plexus.classworlds.launcher.Launcher -f pom.xml -B -V -e -Dfindbugs.skip -Dcheckstyle.skip -Dpmd.skip=true -Dspotbugs.skip -Denforcer.skip -Dmaven.javadoc.skip -DskipTests -Dmaven.test.skip.exec -Dlicense.skip=true -Drat.skip=true -Dspotless.check.skip=true -s /home/REDACTED/work/fhir-gateway-extension/.codeql-scratch/dbs/java/working/settings.xml com.github.ferstl:depgraph-maven-plugin:4.0.3-CodeQL:graph -B -DclasspathScopes=compile -DoutputDirectory=/home/REDACTED/work/fhir-gateway-extension/.codeql-scratch/dbs/java/working/java-standalone-dependency-graph5508499779638860552/${project.groupId}/${project.artifactId} -DgraphFormat=json -Dmaven.ext.class.path=/opt/hostedtoolcache/CodeQL/2.23.3/x64/codeql/java/tools/java-buildless-maven-plugin.jar (dns block)
• jfrog-prod-use1-shared-virginia-main.s3.amazonaws.com
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java --enable-native-access=ALL-UNNAMED -classpath /usr/share/apache-maven-3.9.11/boot/plexus-classworlds-2.9.0.jar -Dclassworlds.conf=/usr/share/apache-maven-3.9.11/bin/m2.conf -Dmaven.home=/usr/share/apache-maven-3.9.11 -Dlibrary.jansi.path=/usr/share/apache-maven-3.9.11/lib/jansi-native -Dmaven.multiModuleProjectDirectory=/home/REDACTED/work/fhir-gateway-extension/fhir-gateway-extension org.codehaus.plexus.classworlds.launcher.Launcher clean compile -DskipTests (dns block)
  • Triggering command: /usr/lib/jvm/temurin-17-jdk-amd64/bin/java -Dfile.encoding=UTF-8 -Xms256M -Xss8M -Djdk.util.zip.disableZip64ExtraFieldValidation=true -Dsun.misc.unsafe.memory.access=allow --add-opens java.base/sun.reflect.annotation=ALL-UNNAMED -Xmx14581m -classpath /opt/hostedtoolcache/CodeQL/2.23.3/x64/codeql/java/tools/semmle-extractor-java.jar:/opt/hostedtoolcache/CodeQL/2.23.3/x64/codeql/java/tools/lombok-javac-extend.jar com.semmle.extractor.java.JavaExtractor --jdk-version 17 --javac-args @@@/home/REDACTED/work/fhir-gateway-extension/.codeql-scratch/dbs/java/log/ext/javac.args (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)