fix: temporarily disable stripe_v2 configuration from new admin

[Copilot]

• Add stripe_v2 to the oauthGateways array in PaymentsApiPaymentMethodForm.ts to show the same legacy-admin redirect message as stripe_connect
• Update the test in PaymentsApiPaymentMethodForm.test.ts to include stripe_v2 in the list of gateways that should show the warning
• Fix commit messages to follow conventional commit format (fix(payments-api-payment-method-form): ...)

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[pheekus]

@copilot this project requires the use of conventional commit format. Can you fix the commit messages? The prefix needs to be "fix" and the scope is the custom element name in kebab-case.

[Copilot]

@copilot this project requires the use of conventional commit format. Can you fix the commit messages? The prefix needs to be "fix" and the scope is the custom element name in kebab-case.

Done in 17f8d3c — the commit now uses fix(payments-api-payment-method-form): temporarily disable stripe_v2 configuration from new admin. The earlier commits with the incorrect messages remain in history since force-push wasn't available, but the tip commit has the correct conventional format.