[TESTS] upgrade tests for storage

(cherry picked from commit 884ca63738)
(cherry picked from commit 0a45d9c37b)

[TESTS] upgrade tests for storage (squash) relative paths

(cherry picked from commit 3bb19285f3)
(cherry picked from commit c640c09e61)
(cherry picked from commit 40ffe2d226)

[UPGRADE] S3 storage and fixtures

(cherry picked from commit c466c9c657)
(cherry picked from commit e80abbe2cd)
(cherry picked from commit 50a47df1d1)

[UPGRADE]  add sanity checks for [storage*] (squash) speedup upgrade tests

(cherry picked from commit f578279cfe)

.forgejo/workflows/upgrade.yml

@@ -0,0 +1,45 @@
+name: upgrade
+
+on:
+  pull_request_review:
+  push:
+    branches:
+      - 'forgejo*'
+      - 'v*/forgejo*'
+
+jobs:
+  upgrade:
+    runs-on: docker
+    container:
+      image: codeberg.org/forgejo/test_env:main
+    steps:
+      - run: apt-get install -y -qq zstd
+
+      - name: cache S3 binaries
+        id: S3
+        uses: https://code.forgejo.org/actions/cache@v3
+        with:
+          path: |
+            /usr/local/bin/minio
+            /usr/local/bin/mc
+            /usr/local/bin/garage
+          key: S3
+
+      - name: skip if S3 cache hit
+        if: steps.S3.outputs.cache-hit != 'true'
+        run: echo no hit
+
+      - uses: https://code.forgejo.org/actions/checkout@v3
+      - uses: https://code.forgejo.org/actions/setup-go@v4
+        with:
+          go-version: "1.21"
+      - run: |
+          git config --add safe.directory '*'
+          chown -R gitea:gitea . /go
+      - run: |
+          su gitea -c 'make deps-backend'
+      - run: |
+          script=$(pwd)/.forgejo/upgrades/test-upgrade.sh
+          $script run dependencies
+          $script clobber
+          su gitea -c "$script test_upgrades"