Send PR results to 'Pull Request' CDash group and add PR ID to build names (#363)

[bartlettroscoe]

See the commit for details.

[bartlettroscoe]

The results for this change are shown in this GHA run and on CDash here:

• https://testing.sandia.gov/cdash/index.php?project=TriBITS&filtercount=1&showfilters=1&field1=buildname&compare1=65&value1=pr-396_

showing these builds in the new "Pull Request" CDash group. This is very nice. This is ready to merge.

[bartlettroscoe]

NOTE: I also ran some experimental builds no 'crf450' by first running:

$ cd ~/Trilinos.base/BUILDS/GCC-4.8.3/TRIBITS_MPI_DEBUG_CMAKE_3.21/
$ . load-env.sh
$ ./do-configure
$ make dashboard

which posted to:

• https://testing.sandia.gov/cdash/index.php?project=TriBITS&parentid=9580222&filtercount=1&showfilters=1&field1=buildstamp&compare1=61&value1=20210722-1519-Experimental&filtercombine=and

and:

$ cd ~/Trilinos.base/BUILDS/GCC-4.8.3/TRIBITS_MPI_DEBUG_CMAKE_3.21/
$ . load-env.sh
$ env CTEST_PARALLEL_LEVEL=16 \
  ~/Trilinos.base/Trilinos/TriBITS/cmake/ctest/github_actions/run_github_actions_ctest_driver.sh \
  --os ubuntu-latest --cmake-ver 3.21.0 --generator makefiles --python-ver 3.8 \
  --cxx-compiler-and-ver g++-9 --fortran-compiler-and-ver gfortran-9

which posted to:

• https://testing.sandia.gov/cdash/index.php?project=TriBITS&parentid=9580224&filtercount=1&showfilters=1&field1=buildstamp&compare1=61&value1=20210722-1519-Experimental&filtercombine=and

The former does not touch any of this GitHub Actions specific logic in #363 while the latter does and shows that it is possible to run the script run_github_actions_ctest_driver.sh locally which posts an experimental build. (This makes it possible to locally develop on and debug that script and not have to hammer and abuse GitHub Actions runners and draw down you allotment of free GHA hours.)