ci: use ghcr image mirrors for postgres and redis services (#6556)

Replaces Docker Hub image references in CI with their
`ghcr.io/getsentry/image-mirror-*` equivalents, consistent with how
`getsentry/sentry` pulls service containers.

## Changes

- `postgres` →
`ghcr.io/getsentry/image-mirror-library-postgres:17-alpine`
- `redis` →
`ghcr.io/getsentry/image-mirror-library-redis:7.0.8-bullseye`

`mysql` and `docker:dind` are not available in the getsentry mirror
([getsentry/image-mirror](https://github.com/getsentry/image-mirror)) so
those are left unchanged.

The change is made in the Jinja template
(`scripts/split_tox_gh_actions/templates/test_group.jinja`); the three
generated workflow files (`test-integrations-dbs.yml`,
`test-integrations-tasks.yml`, `test-integrations-web-1.yml`) are
regenerated by running `python
scripts/split_tox_gh_actions/split_tox_gh_actions.py`.

---
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Co-authored-by: sentry-junior[bot] <264270552+sentry-junior[bot]@users.noreply.github.com>

Author: sl0thentr0py

.github/workflows/test-integrations-dbs.yml

@@ -21,7 +21,7 @@ jobs:
         os: [ubuntu-22.04]
     services:
       postgres:
-        image: postgres
+        image: ghcr.io/getsentry/image-mirror-library-postgres:17-alpine
         env:
           POSTGRES_PASSWORD: sentry
         # Set health checks to wait until postgres has started

.github/workflows/test-integrations-tasks.yml

@@ -21,7 +21,7 @@ jobs:
         os: [ubuntu-22.04]
     services:
       redis:
-        image: redis
+        image: ghcr.io/getsentry/image-mirror-library-redis:7.0.8-bullseye
         options: >-
           --health-cmd "redis-cli ping"
           --health-interval 10s

.github/workflows/test-integrations-web-1.yml

@@ -21,7 +21,7 @@ jobs:
         os: [ubuntu-22.04]
     services:
       postgres:
-        image: postgres
+        image: ghcr.io/getsentry/image-mirror-library-postgres:17-alpine
         env:
           POSTGRES_PASSWORD: sentry
         # Set health checks to wait until postgres has started

scripts/split_tox_gh_actions/templates/test_group.jinja

@@ -17,7 +17,7 @@
       {% endif %}
       {% if needs_postgres %}
       postgres:
-        image: postgres
+        image: ghcr.io/getsentry/image-mirror-library-postgres:17-alpine
         env:
           POSTGRES_PASSWORD: sentry
         # Set health checks to wait until postgres has started
@@ -32,7 +32,7 @@
       {% endif %}
       {% if needs_redis %}
       redis:
-        image: redis
+        image: ghcr.io/getsentry/image-mirror-library-redis:7.0.8-bullseye
         options: >-
           --health-cmd "redis-cli ping"
           --health-interval 10s