[7.15](backport #28457) Check when response content type is nil

[mergify]

This is an automatic backport of pull request #28457 done by Mergify.

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• Start Time: 2021-10-15T18:50:18.755+0000

• Duration: 101 min 31 sec

• Commit: b4d3527

Test stats 🧪

Test	Results
Failed	0
Passed	7773
Skipped	1201
Total	8974

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