fix(deps): update dependency org.assertj:assertj-core to v3.26.0 (open-telemetry#386)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

gradle/libs.versions.toml

@@ -43,7 +43,7 @@ junit-jupiter-api = { module = "org.junit.jupiter:junit-jupiter-api", version.re
 junit-jupiter-engine = { module = "org.junit.jupiter:junit-jupiter-engine", version.ref = "junit" }
 junit-vintage-engine = { module = "org.junit.vintage:junit-vintage-engine", version.ref = "junit" }
 robolectric = "org.robolectric:robolectric:4.12.2"
-assertj-core = "org.assertj:assertj-core:3.25.3"
+assertj-core = "org.assertj:assertj-core:3.26.0"
 awaitility = "org.awaitility:awaitility:4.2.1"
 mockwebserver = "com.google.mockwebserver:mockwebserver:20130706"
 okhttp-mockwebserver = { module = "com.squareup.okhttp3:mockwebserver", version.ref = "okhttp" }