build: Upgrade from Go 1.20 to Go 1.21 (#2665)

Author: kyleconroy

.github/workflows/ci.yml

@@ -12,7 +12,7 @@ jobs:
     - uses: actions/checkout@v3
     - uses: actions/setup-go@v4
       with:
-        go-version: '1.20.7'
+        go-version: '1.21.0'
     - run: go build ./...
 
   darwin-build:
@@ -22,7 +22,7 @@ jobs:
     - uses: actions/checkout@v3
     - uses: actions/setup-go@v4
       with:
-        go-version: '1.20.7'
+        go-version: '1.21.0'
     - run: go build ./...
 
   build:
@@ -53,7 +53,7 @@ jobs:
     - uses: actions/checkout@v3
     - uses: actions/setup-go@v4
       with:
-        go-version: '1.20.7'
+        go-version: '1.21.0'
 
     - name: gotestsum
       run: go install gotest.tools/gotestsum@latest
@@ -92,6 +92,6 @@ jobs:
     - uses: actions/checkout@v3
     - uses: actions/setup-go@v4
       with:
-        go-version: '1.20.7'
+        go-version: '1.21.0'
     - run: go install golang.org/x/vuln/cmd/govulncheck@latest
-    - run: govulncheck ./...
+    - run: govulncheck ./...