Prepare for release v2.7.0, start with v2.7.0-rc1

Since we have never released with goreleaser and GO111MODULE=on
and have removed vendor directory, we are going to push a
v2.7.0-rc1 tag. If the goreleaser process works fine and submit
the draft release correctly, we will not do an actual v2.7.0-rc1
release. Instead, we will follow up immediately with the v2.7.0
tag and the proper release.

Signed-off-by: Ivan Kozlovic <ivan@synadia.com>

.github/workflows/go-test.yaml

@@ -9,7 +9,7 @@ jobs:
 
     env:
       GOPATH: /home/runner/work/nats-server
-      GO111MODULE: "off"
+      GO111MODULE: "on"
 
     runs-on: ubuntu-latest
     steps:
@@ -36,7 +36,7 @@ jobs:
           go build
           $(exit $(go fmt $GO_LIST | wc -l))
           go vet $GO_LIST
-          find . -type f -name "*.go" | grep -v "/vendor/" | xargs $GOPATH/bin/misspell -error -locale US
+          find . -type f -name "*.go" | xargs $GOPATH/bin/misspell -error -locale US
           $GOPATH/bin/staticcheck $GO_LIST
 
       - name: Run tests

.github/workflows/nightly.yaml

@@ -12,7 +12,7 @@ jobs:
 
     env:
       GOPATH: /home/runner/work/nats-server
-      GO111MODULE: "off"
+      GO111MODULE: "on"
 
     steps:
       - name: Checkout code