Updating terraform doc to add note that name of target_instance field…

[aditikumarii-google]

sql: added notes in doc samples to nofify uses that `target_resource` is mandatory field and the target_resource name should match the name of the resource being created.

Doc - https://docs.google.com/document/d/10UBI5l64MmmzV4ghZGMzSNLiNWrMMM1sKfMrVtlAO5o/edit?resourcekey=0-O3iT087a3Jl7FXYU9heTWg&tab=t.0

[github-actions]

Googlers: For automatic test runs see go/terraform-auto-test-runs.

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[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes for commit 487e02b:

Diff report

Your PR generated the following diffs in downstream repositories:

Repository	Diff Link	Changes
google provider	View Diff	1 file changed, 4 insertions(+), 4 deletions(-)
google-beta provider	View Diff	1 file changed, 4 insertions(+), 4 deletions(-)

[NickElliot]

LGTM but are there plans to make these requirements enforced at plantime when breaking changes are being accepted in the next release?