Add application_name to compute activity monitor connection string

[tristan957]

This was missed in my previous attempt to mark every connection string with an application name. See 0c3e3a8.

[github-actions]

2940 tests run: 2823 passed, 0 failed, 117 skipped (full report)

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Flaky tests (2)

Postgres 15

• test_subscriber_restart: release

Postgres 14

• test_location_conf_churn[3]: debug

Code coverage* (full report)

• functions: 32.6% (6892 of 21126 functions)
• lines: 50.0% (53924 of 107903 lines)

* collected from Rust tests only

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_{The comment gets automatically updated with the latest test results
991b192 at 2024-06-27T16:16:37.580Z :recycle:}