Migrate resource_compute_target_pool_test to use transport_tpg.SendRequest

[iliatsuprik]

Release Note Template for Downstream PRs (will be copied)

This change migrates TestAccComputeTargetPool_basic and helper methods to use transport_tpg.SendRequest instead of NewClient

compute: migrated `resource_compute_target_pool_test.go.tmpl` test to use direct HTTP rather than a client library

[modular-magician]

Hi there, I'm the Modular magician. I've detected the following information about your changes for commit 8a65267:

Diff report

Your PR generated the following diffs in downstream repositories:

Repository	Diff Link	Changes
google provider	View Diff	1 file changed, 19 insertions(+), 7 deletions(-)
google-beta provider	View Diff	1 file changed, 19 insertions(+), 7 deletions(-)

Test report

Analytics

Total Tests	Passed	Skipped	Affected
1428	1337	91	0

Affected Service Packages

• compute

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@iliatsuprik VCR tests complete for 8a65267!

[github-actions]

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