Fix: external_data_configuration.connection_id Diff Suppression

[modular-magician]

Fixes: #12386

Mentioned in; #12465

Changes

• Add: Test Coverage for name and id references in External Data Configuration
• Fix: case sensitivity in location for connection id. In the slash and dot forms of connection id the region has different case. Change the comparison to be case insensittive

Release Note Template for Downstream PRs (will be copied)

bigquery: fix diff suppression in `external_data_configuration.connection_id`

Derived from GoogleCloudPlatform/magic-modules#9053

[github-actions]

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