docs: fix sonar links

Signed-off-by: Clement Bois <clement.bois@orange.com>

README.md

@@ -83,7 +83,7 @@ More info:
 
 - [Rust language support](https://docs.sonarqube.org/latest/analysis/languages/rust/)
 - [test coverage & execution parameters](https://docs.sonarqube.org/latest/analysis/coverage/)
-- [third-party issues](https://docs.sonarqube.org/latest/analysis/external-issues/)
+- [third-party issues](https://docs.sonarsource.com/sonarqube-server/latest/analyzing-source-code/importing-external-issues/external-analyzer-reports/)
 
 ### `rust-lint` job