refactor: integrate more probe-engine workflows

This diff is part of ooni/probe#1335.

We are moving more probe-engine workflows to toplevel.

The general idea here is to migrate all possible workflows and to
delete the ones that we cannot use in this repo (if any).

internal/engine/.github/workflows/alltests.yml → .github/workflows/alltests.yml

@@ -13,4 +13,4 @@ jobs:
         with:
           go-version: "1.14"
       - uses: actions/checkout@v2
-      - run: go test -race -tags integration,shaping -coverprofile=probe-engine.cov ./...
+      - run: go test -race -tags shaping ./...

internal/engine/.github/workflows/coverage.yml → .github/workflows/coverage.yml

@@ -15,10 +15,10 @@ jobs:
         with:
           go-version: "${{ matrix.go }}"
       - uses: actions/checkout@v2
-      - run: go test -short -race -tags shaping -coverprofile=probe-engine.cov ./...
+      - run: go test -short -race -tags shaping -coverprofile=probe-cli.cov ./...
       - uses: shogo82148/actions-goveralls@v1
         with:
-          path-to-profile: probe-engine.cov
+          path-to-profile: probe-cli.cov
           parallel: true
   finish:
     needs: test