Consolidate lint steps in GitHub Actions

Like with running Go tests, the lints for each separate Go module must
be running separately. This is currently being accomplished in CI by
giving each Go module its own lint job using golangci-lint's GitHub
Action.

Unfortunately, this is really not working out well. Although the lints
themselves are all very fast to run (just a couple seconds), the post
run step where it saves it cache is quite slow, about two minutes, and
that's happening for each of the lint steps, making the entire lint job
take almost _ten minutes_ to run.

Here, try to hack around the problem by having the main lint job fetch
golangci-lint, but then only run `--help`, and then do the real linting
as a separate step (one that doesn't use the GitHub Action) that calls
into our `make lint` target to run lints for each Go module.

A downside is that it may not annotate lint problems on the GitHub PR,
which is something that theoretically happened before, although it never
seemed to work for me. This might not be that bad though because it
could as a side effect improve the log output, which is terrible for the
GitHub Action step because it doesn't include files or line numbers.

[1] golangci/golangci-lint-action#271

.github/workflows/ci.yml

@@ -164,37 +164,9 @@ jobs:
         uses: golangci/golangci-lint-action@v4
         with:
           version: ${{ env.GOLANGCI_LINT_VERSION }}
-          working-directory: .
 
-      - name: Lint cmd/river
-        uses: golangci/golangci-lint-action@v4
-        with:
-          version: ${{ env.GOLANGCI_LINT_VERSION }}
-          working-directory: ./cmd/river
-
-      - name: Lint riverdriver
-        uses: golangci/golangci-lint-action@v4
-        with:
-          version: ${{ env.GOLANGCI_LINT_VERSION }}
-          working-directory: ./riverdriver
-
-      - name: Lint riverdriver/riverdatabasesql
-        uses: golangci/golangci-lint-action@v4
-        with:
-          version: ${{ env.GOLANGCI_LINT_VERSION }}
-          working-directory: ./riverdriver/riverdatabasesql
-
-      - name: Lint riverdriver/riverpgxv5
-        uses: golangci/golangci-lint-action@v4
-        with:
-          version: ${{ env.GOLANGCI_LINT_VERSION }}
-          working-directory: ./riverdriver/riverpgxv5
-
-      - name: Lint rivertype
-        uses: golangci/golangci-lint-action@v3
-        with:
-          version: ${{ env.GOLANGCI_LINT_VERSION }}
-          working-directory: ./rivertype
+      - name: Run lint
+        run: make lint
 
   producer_sample:
     runs-on: ubuntu-latest