CMake: Build standalone tests out of source in Coin

Due to a bug in upstream CMake regarding relative paths being encoded
into the build.ninja file when performing in source builds, we need to
build the tests in a standalone directory outside of the source
directory.

Failing to do so will cause the source directory for the test to be
incorrect which can cause tests to fails and never read the
BLACKLIST.txt file. See the mentioned issue for details.

Task-number: QTBUG-82820
Change-Id: Ie5c178a92369d6b9decff625bd9641e53088a9fa
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

coin/instructions/cmake_build_and_upload_test_artifacts.yaml

@@ -3,9 +3,9 @@ instructions:
   - type: ChangeDirectory
     directory: "{{.SourceDir}}"
   - type: MakeDirectory
-    directory: "standalone_tests"
+    directory: "{{.SourceDir}}_standalone_tests"
   - type: SetBuildDirectory
-    directory: "{{.SourceDir}}/standalone_tests"
+    directory: "{{.SourceDir}}_standalone_tests"
   - type: ChangeDirectory
     directory: "{{.BuildDir}}"
   - type: EnvironmentVariable

coin/instructions/cmake_regular_test_instructions.yaml

@@ -1,18 +1,16 @@
 type: Group
 instructions:
-  - type: ChangeDirectory
-    directory: "{{.SourceDir}}"
   - type: MakeDirectory
-    directory: "standalone_tests"
+    directory: "{{.SourceDir}}_standalone_tests"
   - type: InstallTestBinaryArchive
     relativeStoragePath: "{{.Env.MODULE_ARTIFACTS_RELATIVE_STORAGE_PATH}}/tests.tar.gz"
-    directory: "{{.SourceDir}}/standalone_tests"
+    directory: "{{.SourceDir}}_standalone_tests"
     maxTimeInSeconds: 1200
     maxTimeBetweenOutput: 1200
     userMessageOnFailure: >
       Failed to install tests archive.
   - type: ChangeDirectory
-    directory: "{{.SourceDir}}/standalone_tests"
+    directory: "{{.SourceDir}}_standalone_tests"
   - type: ExecuteCommand
     command: "ctest -V --rerun-failed"
     ignoreExitCode: true