Merge branch 'topic/fix_testsuite_baseline' into 'master'

Update test baselines following GPR2 message changes

Closes #460

See merge request eng/libadalang/langkit-query-language!427

Author: HugoGGuerrier

testsuite/tests/gnatcheck_errors/wrong_runtime/linux/test.out

@@ -1,5 +1,5 @@
 testsuite_driver: No output file generated by gnatcheck
-kb: warning: can't find a toolchain for the following configuration: language 'Ada', target 'x86_64-linux', runtime 'unknown'
+kb: info: can't find a toolchain for the following configuration: language 'Ada', target 'x86_64-linux', runtime 'unknown'
 gnatcheck: error: "prj.gpr" processing failed
 try "gnatcheck --help" for more information.
 >>>program returned status code 2

testsuite/tests/gnatcheck_errors/wrong_runtime/windows/test.out

@@ -1,5 +1,5 @@
 testsuite_driver: No output file generated by gnatcheck
-kb: warning: can't find a toolchain for the following configuration: language 'Ada', target 'x86_64-windows', runtime 'unknown'
+kb: info: can't find a toolchain for the following configuration: language 'Ada', target 'x86_64-windows', runtime 'unknown'
 gnatcheck: error: "prj.gpr" processing failed
 try "gnatcheck --help" for more information.
 >>>program returned status code 2

testsuite/tests/gnatcheck_errors/wrong_target/test.out

@@ -1,5 +1,5 @@
 testsuite_driver: No output file generated by gnatcheck
-kb: warning: can't find a toolchain for the following configuration: language 'Ada', target 'wrong', default runtime
+kb: info: can't find a toolchain for the following configuration: language 'Ada', target 'wrong', default runtime
 gnatcheck: error: "prj.gpr" processing failed
 try "gnatcheck --help" for more information.
 >>>program returned status code 2