SONARPHP-1627 Add information about plugin-api update requirements (#1371)

Co-authored-by: GabinL21 <[email protected]>

Author: jonas-wielage-sonarsource

gradle/libs.versions.toml

@@ -1,5 +1,7 @@
 [versions]
 sonar-commons = "2.16.0.3141"
+# Before updating the plugin-api version, make sure to check the compatibility matrix and stick to the lowest denominator
+# https://github.com/SonarSource/sonar-plugin-api?tab=readme-ov-file#compatibility
 sonar-plugin-api = "11.1.0.2693"
 sonarqube = "24.12.0.100206"
 sonar-scanner-gradle = "6.0.1.5171"