Update deployment-tools.rst

Added"Check requirements as A  in Common Post-Deployment Tasks
some minor improvements
feature #4124 Rebased #3965 (WouterJ)

This PR was merged into the 2.3 branch.

Discussion
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Rebased #3965

Rebased version of @j00seph's PR: #3965

Commits
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d8dc7aa some minor improvements
70b7d41 Update deployment-tools.rst