raise Go version for internal CI pipelines

.github/workflows/run_e2e.yaml

@@ -14,7 +14,7 @@ jobs:
     - uses: actions/checkout@v1
     - uses: actions/setup-go@v2
       with:
-          go-version: "^1.15.6"
+          go-version: "^1.16.9"
     - name: Make dependencies
       run: make deps mocks
     - name: Compile

.github/workflows/run_tests.yaml

@@ -14,7 +14,7 @@ jobs:
     - uses: actions/checkout@v2
     - uses: actions/setup-go@v2
       with:
-          go-version: "^1.15.6"
+          go-version: "^1.16.9"
     - name: Make dependencies
       run: make deps mocks
     - name: Compile

delivery.yaml

@@ -16,7 +16,7 @@ pipeline:
         - desc: 'Install go'
           cmd: |
             cd /tmp
-            wget -q https://storage.googleapis.com/golang/go1.15.6.linux-amd64.tar.gz -O go.tar.gz
+            wget -q https://storage.googleapis.com/golang/go1.16.9.linux-amd64.tar.gz -O go.tar.gz
             tar -xf go.tar.gz
             mv go /usr/local
             ln -s /usr/local/go/bin/go /usr/bin/go

docs/developer.md

@@ -7,7 +7,7 @@ features and tests.
 
 Postgres Operator is written in Go. Use the [installation instructions](https://golang.org/doc/install#install)
 if you don't have Go on your system. You won't be able to compile the operator
-with Go older than 1.15. We recommend installing [the latest one](https://golang.org/dl/).
+with Go older than 1.16. We recommend installing [the latest one](https://golang.org/dl/).
 
 Go projects expect their source code and all the dependencies to be located
 under the [GOPATH](https://github.com/golang/go/wiki/GOPATH). Normally, one