Rename Type: Test-Failure Label [DI-266] (#719)

_Partially addresses:_
[DI-266](https://hazelcast.atlassian.net/browse/DI-266)

[DI-266]:
https://hazelcast.atlassian.net/browse/DI-266?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

Author: JackPGreen

.github/ISSUE_TEMPLATE/test-failure-report.md

@@ -2,7 +2,7 @@
 name: Test Failure report
 about: Template for test failures
 title: INSERT_FULL_TEST_NAME_HERE
-labels: ['Type: Test-Failure']
+labels: ['Type: Test Failure']
 assignees: ''
 ---