ByteStreamCnvSvc: CMake fix

Fix the following:

CMake Error at /cvmfs/atlas-nightlies.cern.ch/repo/sw/master_Athena_x86_64-centos7-gcc8-opt/2021-05-11T2101/Athena/22.0.35/InstallArea/x86_64-centos7-gcc8-opt/cmake/modules/AtlasTestFunctions.cmake:38 (add_executable):
  Target "ByteStreamCnvSvc_ByteStreamMetadataToolTest" links to target
  "GTest::gtest" but the target was not found.  Perhaps a find_package() call
  is missing for an IMPORTED target, or an ALIAS target is missing?

which is seen in local partial (WorkDir) builds of the package.

Not sure why it's never an issue in CI / full builds (@akraszna?)

MR submitted from GitLab web editor

This merge request affects 1 package:

• Event/ByteStreamCnvSvc

This merge request affects 1 file:

• Event/ByteStreamCnvSvc/CMakeLists.txt

Adding @tadej as watcher

added EDM master review-pending-level-1 labels

cc @berghaus

I'm not actually sure why it's not a problem in the full build.

FindGTest.cmake does not set up the imported targets to be "global". (https://cmake.org/cmake/help/latest/command/add_library.html#imported-libraries) So just because some other package calls find_package(GTest), the imported targets should not be visible to this piece of code.

Something upstream from this package must be calling find_package(GTest) in full Athena builds, but I can't find what it is... Which starts to annoy me quite a bit.

But in the end this is definitely a good update, so even if we don't understand exactly why the issue didn't show up before, this still needs to go in.

added bugfix label

@rbielski thank you for the fix, and I am also mystified why this did not show before.

Maybe the google test suite came in from the tdaq externals that are used here? Just having a gander through there.

CI Result SUCCESS (hash a38dcdcd)

	Athena	AthSimulation	AthGeneration	AnalysisBase	AthAnalysis	DetCommon
externals
cmake
make
required tests
optional tests

Full details available on this CI monitor view
Athena: number of compilation errors 0, warnings 0
AthSimulation: number of compilation errors 0, warnings 0
AthGeneration: number of compilation errors 0, warnings 0
AnalysisBase: number of compilation errors 0, warnings 0
AthAnalysis: number of compilation errors 0, warnings 0
DetCommon: number of compilation errors 0, warnings 0
For experts only: Jenkins output [CI-MERGE-REQUEST-CC7 33432]

Clear, approving.

Pavol [as L2 MR shifter]

added review-approved label and removed review-pending-level-1 label

merged

mentioned in commit 784ca5ce

added sweep:ignore label