[RS] Skip NaNs and infinities in HypoTestInverter.

[hageboeck]

If a fit fails, it might produce non-finite confidence levels. This can
be a problem for the hypothesis test inversion.
Here, all non-finite numbers are skipped, in the hope that this can
stabilise a limit calculation in cases where the failed fits are
irrelevant for finding the 95% CL.

[phsft-bot]

Starting build on ROOT-debian10-i386/cxx14, ROOT-performance-centos7-multicore/default, ROOT-fedora30/cxx14, ROOT-fedora31/noimt, ROOT-ubuntu16/nortcxxmod, mac1014/python3, mac1015/cxx17, windows10/cxx14
How to customize builds

[phsft-bot]

Build failed on ROOT-fedora30/cxx14.
Running on root-fedora30-1.cern.ch:/build/workspace/root-pullrequests-build
See cdash.
See console output.

Failing tests:

• projectroot.roottest.cling.functionTemplate.roottest_cling_functionTemplate_testcint

[phsft-bot]

Build failed on mac1014/python3.
Running on macitois21.cern.ch:/build/jenkins/workspace/root-pullrequests-build
See cdash.
See console output.

Failing tests:

• projectroot.roottest.root.meta.evolution.roottest_root_meta_evolution_execMixedBaseClass_v2
• projectroot.roottest.root.meta.tclass.roottest_root_meta_tclass_execTmpltD

[lmoneta]

LGTM

[phsft-bot]

Starting build on ROOT-debian10-i386/cxx14, ROOT-performance-centos7-multicore/default, ROOT-fedora30/cxx14, ROOT-fedora31/noimt, ROOT-ubuntu16/nortcxxmod, mac1014/python3, mac1015/cxx17, windows10/cxx14
How to customize builds

[phsft-bot]

Build failed on ROOT-fedora30/cxx14.
Running on root-fedora30-1.cern.ch:/build/workspace/root-pullrequests-build
See cdash.
See console output.

Failing tests:

• projectroot.roottest.cling.functionTemplate.roottest_cling_functionTemplate_testcint

[phsft-bot]

Build failed on mac1014/python3.
Running on macitois19.cern.ch:/ec/build/workspace/root-pullrequests-build
See cdash.
See console output.

Failing tests:

• projectroot.roottest.python.JupyROOT.roottest_python_JupyROOT_handlers_doctest