Bump to go 1.21

The upstream `moby` bug that triggered the temp pin has been fixed:
* #156
* docker/cli#4437

So no need to pin to specific patch versions anymore.

Update to `go` `1.21` while I was in there.

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v4
         with:
-          go-version: 1.20.5
+          go-version: 1.21
 
       - name: Build
         run: go build -v ./...
@@ -30,7 +30,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v4
         with:
-          go-version: 1.20.5
+          go-version: 1.21
 
       - name: Run go vet
         run: go vet ./...
@@ -50,7 +50,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v4
         with:
-          go-version: 1.20.5
+          go-version: 1.21
 
       - name: Run integration tests
         run: tests/local

.github/workflows/release.yml

@@ -24,7 +24,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: wangyoucao577/[email protected]
         with:
-          goversion: 1.20.5
+          goversion: 1.21
           github_token: ${{ secrets.GITHUB_TOKEN }}
           goos: ${{ matrix.goos }}
           goarch: ${{ matrix.goarch }}

.github/workflows/smoke.yml

@@ -46,7 +46,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v4
         with:
-          go-version: 1.20.5
+          go-version: 1.21
 
       # Download the Proxy cache. The job is ideally 100% cached so no real calls are made.
       - name: Download cache

go.mod

@@ -1,6 +1,6 @@
 module github.com/dependabot/cli
 
-go 1.20
+go 1.21
 
 require (
 	github.com/MakeNowJust/heredoc v1.0.0

internal/infra/run_test.go

@@ -242,7 +242,7 @@ func TestRun(t *testing.T) {
 }
 
 const dockerFile = `
-FROM golang:1.20.5
+FROM golang:1.21
 
 # needed to run update-ca-certificates
 RUN apt-get update && apt-get install -y ca-certificates