chore(cloudflare): migrate customhostname to v5

[AndrewCharlesHay]

What does it do ?

Migrate customhostname to v5

Motivation

Closes #5540

More

• Yes, this PR title follows Conventional Commits
• Yes, I added unit tests
• Yes, I updated end user documentation accordingly

[k8s-ci-robot]

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[coveralls]

Pull Request Test Coverage Report for Build 18312219767

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

• For more information on this, see Tracking coverage changes with pull request builds.
• To avoid this issue with future PRs, see these Recommended CI Configurations.
• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 72 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.03%) to 78.52%

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Files with Coverage Reduction	New Missed Lines	%
openshift_route.go	1	79.49%
cloudflare/cloudflare.go	71	89.73%

Totals
Change from base Build 18242454154:	-0.03%
Covered Lines:	15806
Relevant Lines:	20130

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💛 - Coveralls