[GCP] Convert GCP Firestore metricset from lightweight

[legoguy1000]

What does this PR do?

Convert GCP Firestore metricset from lightweight

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.

Author's Checklist

• [ ]

How to test this PR locally

Related issues

• Closes [GCP] Remove lightweight module in gcp.firestore data stream #3722

Screenshots

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Build stats

• Start Time: 2022-09-19T18:36:40.828+0000

• Duration: 18 min 52 sec

Test stats 🧪

Test	Results
Failed	0
Passed	82
Skipped	0
Total	82

🤖 GitHub comments

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[kaiyan-sheng]

/test

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (5/5)	💚
Files	100.0% (5/5)	💚
Classes	100.0% (5/5)	💚
Methods	90.816% (89/98)	❕
Lines	95.752% (1375/1436)	❕
Conditionals	100.0% (0/0)	💚

[legoguy1000]

Seems good to merge?

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🚀 Benchmarks report

Package gcp 👍(4) 💚(0) 💔(1)

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Data stream	Previous EPS	New EPS	Diff (%)	Result
loadbalancing_logs	3663	2801.12	-861.88 (-30.77%)	💔

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