[chore] Upgrade our Go version to 1.22 (#2862)

* [chore] Upgrade our Go version to 1.22

With Go 1.22 having been released at the start of February, it's now
been a few months. No major issues have shown up, and the two point
release since then have primarily been security fixes plus some general
bug fixing.

This sets the required Go version to 1.22, as there's nothing in 1.22.1
or 1.22.2 that we would explicitly require. It sets the toolchain to the
latest point release, to ensure we pick up any fixes from there when
building releases etc.

* [chore] Update CI to Go 1.22

* [chore] Update golangci-lint to 1.25.7

Newer version should know about Go 1.22 and run fine.

* [chore] Update Docker container to Go 1.22

* [chore] Update Dockerfile to newer Alpine version

* sign drone.yml

* add missing license header

---------

Co-authored-by: tobi <tobi.smethurst@protonmail.com>

.drone.yml

@@ -12,7 +12,7 @@ steps:
   # We use golangci-lint for linting.
   # See: https://golangci-lint.run/
   - name: lint
-    image: golangci/golangci-lint:v1.55.0
+    image: golangci/golangci-lint:v1.57.2
     volumes:
       - name: go-build-cache
         path: /root/.cache/go-build
@@ -28,7 +28,7 @@ steps:
           - pull_request
 
   - name: test
-    image: golang:1.21-alpine
+    image: golang:1.22-alpine
     volumes:
       - name: go-build-cache
         path: /root/.cache/go-build
@@ -80,7 +80,7 @@ steps:
       - yarn --cwd ./web/source build
 
   - name: snapshot
-    image: superseriousbusiness/gotosocial-drone-build:0.4.0 # https://github.com/superseriousbusiness/gotosocial-drone-build
+    image: superseriousbusiness/gotosocial-drone-build:0.5.0 # https://github.com/superseriousbusiness/gotosocial-drone-build
     volumes:
       - name: go-build-cache
         path: /root/.cache/go-build
@@ -121,7 +121,7 @@ steps:
           - main
 
   - name: release
-    image: superseriousbusiness/gotosocial-drone-build:0.4.0 # https://github.com/superseriousbusiness/gotosocial-drone-build
+    image: superseriousbusiness/gotosocial-drone-build:0.5.0 # https://github.com/superseriousbusiness/gotosocial-drone-build
     volumes:
       - name: go-build-cache
         path: /root/.cache/go-build
@@ -180,7 +180,7 @@ clone:
 
 steps:
   - name: mirror
-    image: superseriousbusiness/gotosocial-drone-build:0.4.0
+    image: superseriousbusiness/gotosocial-drone-build:0.5.0
     environment:
       ORIGIN_REPO: https://github.com/superseriousbusiness/gotosocial
       TARGET_REPO: https://codeberg.org/superseriousbusiness/gotosocial
@@ -193,6 +193,6 @@ steps:
 
 ---
 kind: signature
-hmac: 4789cebf9156b2c3cb0f097311ea7620e709e4332f130dcae51a938515dc952e
+hmac: f7ef1e0d3d4fe0a55d43ba0ab5ed6cb5f5c8bf00791464ce7b251a3cdbfd954a
 
 ...