gha: use stable/oldstable go versions

actions/setup-go supports specifying the latest and latest-1 versions
this way, which is preferable to updating the workflow each time there's
an update. We keep the versions we care about for compatibility
purposes, of course.

Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>

.github/workflows/ci.yml

@@ -46,8 +46,8 @@ jobs:
           - "1.18"
           - "1.20"
           - "1.21"
-          - "1.22"
-          - "^1"
+          - "oldstable"
+          - "stable"
     runs-on: windows-latest
     steps:
       - uses: actions/checkout@v4
@@ -98,8 +98,8 @@ jobs:
           - "1.18"
           - "1.20"
           - "1.21"
-          - "1.22"
-          - "^1"
+          - "oldstable"
+          - "stable"
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v4
@@ -133,7 +133,7 @@ jobs:
       - uses: actions/checkout@v4
       - uses: actions/setup-go@v5
         with:
-          go-version: "^1"
+          go-version: "stable"
       - name: download all coverage
         uses: actions/download-artifact@v4
         with: