Update CONTRIBUTING.md to document Java 17 requirement. (#8819)

Author: tylerbenson

CONTRIBUTING.md

@@ -8,7 +8,7 @@ and discuss your ideas or propose the changes you wish to make.
 
 ## Building
 
-In order to build and test this whole repository you need JDK 17 or higher.
+This project requires Java 17 to build and run tests. Newer JDK's may work, but this version is used in CI.
 
 Some instrumentations and tests may put constraints on which java versions they support.
 See [Running the tests](./docs/contributing/running-tests.md) for more details.
@@ -22,7 +22,7 @@ the Sonatype OSS snapshots repository at `https://oss.sonatype.org/content/repos
 
 ### Building from source
 
-Build using Java 17+:
+Build using Java 17:
 
 ```bash
 java -version