Fix linux mapping in linux.vmstat types

[fearful-symmetry]

What does this PR do?

This is hopefully a fix for #3120

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

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Build stats

• Start Time: 2022-05-24T19:45:55.253+0000

• Duration: 19 min 44 sec

Test stats 🧪

Test	Results
Failed	0
Passed	25
Skipped	0
Total	25

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (0/0)	💚
Files	100.0% (0/0)	💚 3.695
Classes	100.0% (0/0)	💚 3.695
Methods	51.515% (17/33)	👎 -36.655
Lines	100.0% (0/0)	💚 10.251
Conditionals	100.0% (0/0)	💚