drop public submodule replace directive (#24045)

* drop public submodule replace directive

During development of the public/ submodule, a replace directive remained that was both unnecessary and harmful as discussed in https://community.mattermost.com/private-core/pl/w77sh7igwpfb9ecj5o4jjjbbyo.

Remove that, and bump the explicit dependency (even though we use go.work) to v0.0.6 so the import paths match (e.g. `mattermost` vs `mattermost-server`).

* make modules-tidy

* consistently setup-go-work

* fix build-api-spec

* fix mmctl test template

* fix workflow copy/paste typo

.github/workflows/mmctl-test-template.yml

@@ -30,6 +30,10 @@ jobs:
         uses: actions/setup-go@4d34df0c2316fe8122ab82dc22947d607c0c91f9 # v4.0.0
         with:
           go-version: ${{ env.go-version }}
+      - name: Run setup-go-work
+        run: |
+          cd server
+          make setup-go-work
       - name: Run docker compose
         run: |
           cd server/build