[HttpCache] added a test (cached content should be kept after purging)
merged branch bamarni/issue-6830 (PR #7408)

This PR was merged into the 2.1 branch.

Commits
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54609b9 [HttpCache] added a test (cached content should be kept after purging)

Discussion
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[HttpCache] added a test (cached content should be kept after purging)

closes #6830