Fix typo in google_monitoring_uptime_check_config

[rwblokzijl]

Fixes a typo to make the spec match https://cloud.google.com/monitoring/api/ref_v3/rest/v3/projects.uptimeCheckConfigs#contentmatcheroption

fixes: hashicorp/terraform-provider-google#10106

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Release Note Template for Downstream PRs (will be copied)

monitoring: fixed typo in `google_monitoring_uptime_check_config` where `NOT_MATCHES_REGEX` could not be specified.

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[modular-magician]

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[rwblokzijl]

@googlebot I signed it!

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))
Terraform Beta: Diff ( 3 files changed, 4 insertions(+), 5 deletions(-))

[megan07]

/gcbrun

[modular-magician]

Hi! I'm the modular magician. Your PR generated some diffs in downstreams - here they are.

Diff report:

Terraform GA: Diff ( 2 files changed, 3 insertions(+), 3 deletions(-))
Terraform Beta: Diff ( 3 files changed, 4 insertions(+), 4 deletions(-))

[modular-magician]

I have triggered VCR tests in RECORDING mode for the following tests that failed during VCR: TestAccServiceNetworkingPeeredDNSDomain_basic You can view the result here: https://ci-oss.hashicorp.engineering/viewQueued.html?itemId=209150

[megan07]

Looks good! Thank you!