Adding workflow to automatically create typo PRs (cosmos#5724)

* chore: adding workflow and note in CONTRIBUTING.md

* chore: clean up workflow

* Update CONTRIBUTING.md

---------

Co-authored-by: Carlos Rodriguez <carlos@interchain.io>

.github/.misspell-fixer.ignore

@@ -0,0 +1 @@
+\*.pb.go

.github/workflows/spell-checker.yml

@@ -0,0 +1,25 @@
+name: Fix typos nightly
+
+on:
+  workflow_dispatch: {} # enable manual running of workflow.
+  schedule:
+    - cron: "0 8 * * *"
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - uses: sobolevn/misspell-fixer-action@e5368f1b21585248afad4d32df9bc100451dbbff
+      - uses: peter-evans/create-pull-request@v5
+        with:
+          token: ${{ secrets.GITHUB_TOKEN }}
+          commit-message: "chore: fixes by misspell-fixer"
+          title: "chore: typos fix by misspell-fixer"
+          branch: "bot/fix-typos"
+          delete-branch: true
+          body: |
+            This PR fixes typos in the codebase.
+            Please, review it and merge if everything is fine.
+            If there are proto changes, please, run `make proto-all` and commit changes.

CONTRIBUTING.md

@@ -52,6 +52,10 @@ If you would like to contribute, follow this process:
 
 Please make sure to check out our [Pull request guidelines](./docs/dev/pull-requests.md) for more information.
 
+> Note: At this time, we will not be accepting contributions that only fix spelling
+> or grammar errors in documentation, code or elsewhere. The repository has a nightly job that
+> spell checks all files and will automatically open PRs for any spelling errors.
+
 ## Relevant development docs
 
 - [Project structure](./docs/dev/project-structure.md)