feat(outputs.stackdriver): Ensure quota is charged to configured project

[crflanigan]

• Updated Stackdriver output plugin to use the project field from the Telegraf configuration for quota attribution via option.WithQuotaProject(s.Project).
• Ensures that metric ingestion quota is billed to the destination project rather than the service account’s project.
• This allows sending metrics to multiple projects while ensuring that each project is responsible for its own quota, instead of charging all usage to the service account’s project.
• Preserves existing behavior while improving clarity and correctness in quota handling.

Summary

Checklist

• No AI generated code was used in this PR

Related issues

resolves #16584

[telegraf-tiger]

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DEB	RPM	TAR GZ	ZIP
amd64.deb	aarch64.rpm	darwin_amd64.tar.gz	windows_amd64.zip
arm64.deb	armel.rpm	darwin_arm64.tar.gz	windows_arm64.zip
armel.deb	armv6hl.rpm	freebsd_amd64.tar.gz	windows_i386.zip
armhf.deb	i386.rpm	freebsd_armv7.tar.gz
i386.deb	ppc64le.rpm	freebsd_i386.tar.gz
mips.deb	riscv64.rpm	linux_amd64.tar.gz
mipsel.deb	s390x.rpm	linux_arm64.tar.gz
ppc64el.deb	x86_64.rpm	linux_armel.tar.gz
riscv64.deb		linux_armhf.tar.gz
s390x.deb		linux_i386.tar.gz
		linux_mips.tar.gz
		linux_mipsel.tar.gz
		linux_ppc64le.tar.gz
		linux_riscv64.tar.gz
		linux_s390x.tar.gz

[srebhan]

Thanks @crflanigan! Just a single comment...

[srebhan]

I think the default is empty isn't it? So how about shortening this to

Suggested change

	## Quota Project
	## Specifies the Google Cloud project that should be charged for metric ingestion quota.
	## If omitted, the quota is charged to the project associated with the service account.
	## This is useful when sending metrics to multiple projects using a single service account,
	## ensuring that the target projects are billed instead of the service account's project.
	##
	## The caller must have the `serviceusage.services.use` permission on the specified quota project.
	# quota_project = "billing-project"
	## Quota Project to charge for metric ingestion quota
	## If omitted, the quota is charged to the project associated with the service account.
	## The caller must have the `serviceusage.services.use` permission on the specified quota project.
	# quota_project = ""

[crflanigan]

Hey there! So I guess the only concern I would have is that we removed the explanation as to what this would be used for, sending to multiple projects using a single SA while pointing the quota at the destination project instead of the SA project.

How about this?

## Quota Project
## Specifies the Google Cloud project that should be billed for metric ingestion.
## If omitted, the quota is charged to the service account’s default project.
## This is useful when sending metrics to multiple projects using a single service account.
## The caller must have the `serviceusage.services.use` permission on the specified project.
# quota_project = ""