Add Go 1.20 and update action/setup-go to v4 in CI

Signed-off-by: Austin Vazquez <macedonv@amazon.com>

.github/workflows/build.yaml

@@ -17,7 +17,7 @@ jobs:
 
     strategy:
       matrix:
-        go: ['1.17', '1.18', '1.19']
+        go: ['1.17', '1.18', '1.19', '1.20']
       # Build all variants regardless of failures
       fail-fast: false
     name: Go ${{ matrix.go }}
@@ -36,7 +36,7 @@ jobs:
           # So we need to fetch 21 commits (including the merge commit)
           # to have 20 actual commits from a pull request.
           fetch-depth: 21
-      - uses: actions/setup-go@v3
+      - uses: actions/setup-go@v4
         with:
           go-version: ${{ matrix.go }}
       - run: make deps