use go 1.16 to test/build

Author: adarobin

.github/workflows/release.yml

@@ -28,7 +28,7 @@ jobs:
         name: Set up Go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.15
+          go-version: 1.16
       -
         name: Import GPG key
         id: import_gpg

.github/workflows/test.yml

@@ -26,7 +26,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v2.1.3
       with:
-        go-version: '1.15'
+        go-version: '1.16'
       id: go
 
     - name: Check out code into the Go module directory
@@ -59,7 +59,7 @@ jobs:
     - name: Set up Go
       uses: actions/setup-go@v2.1.3
       with:
-        go-version: '1.15'
+        go-version: '1.16'
       id: go
 
     - name: Check out code into the Go module directory