MINOR FIX: IS_RELEASE_CANDIDATE

[cjdutoit]

To verify that IS_RELEASE_CANDIDATE is still true for all conditions.

From @glhays:
I found in some of my testing that these lines
"startsWith(github.event.pull_request.title, 'RELEASES:') &&\r"
"contains(github.event.pull_request.labels.*.name, 'RELEASES')",
can fail especially the contains when the label is RELEASES and the expression contains does not evaluate to true, but if you change it to RELEASE it does as in the EnviromentVariables expression for the RELEASE CANDIDATE check.
When I removed the created release tag and reran the failed action it went through without a RELEASE label.