Update GH Actions to use 1.16

Amends commit 365bb3c.

Author: bkircher

.github/workflows/go.yml

@@ -14,7 +14,7 @@ jobs:
       - name: Set up Golang environment
         uses: actions/setup-go@v2
         with:
-          go-version: 1.15
+          go-version: 1.16
         id: go
 
       - name: Check out code into the Go module directory

.github/workflows/release.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.15
+          go-version: 1.16
 
       - name: Prepare GPG key
         run: |