[8.7](backport #2298) Restore support for the memcached/metrics input.

[mergify]

This is an automatic backport of pull request #2298 done by Mergify.

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• Start Time: 2023-02-21T19:19:48.836+0000

• Duration: 17 min 47 sec

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Test	Results
Failed	0
Passed	4919
Skipped	15
Total	4934

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	98.361% (60/61)	👍
Files	68.9% (144/209)	👍
Classes	68.08% (273/401)	👍
Methods	53.517% (837/1564)	👍
Lines	38.798% (9166/23625)	👎 -0.021
Conditionals	100.0% (0/0)	💚