Change V4 Images heading to 'V4 Images - Test'

[michaelmeaney]

Updated section heading for V4 Images to indicate testing.

Releasing new Host versions.
V3 Release
V2 Release

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PR information

• The title of the PR is clear and informative.
• There are a small number of commits, each of which has an informative message. This means that previously merged commits do not appear in the history of the PR. For information on cleaning up the commits in your pull request, see this page.
• If applicable, the PR references the bug/issue that it fixes in the description.
• New Unit tests were added for the changes made and CI is passing.