Bump r-lib/actions from 2.8.7 to 2.9.0 (#234)

Bumps [r-lib/actions](https://github.com/r-lib/actions) from 2.8.7 to 2.9.0.
- [Release notes](https://github.com/r-lib/actions/releases)
- [Changelog](https://github.com/r-lib/actions/blob/v2-branch/NEWS.md)
- [Commits](r-lib/actions@v2.8.7...v2.9.0)

---
updated-dependencies:
- dependency-name: r-lib/actions
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/docs.yaml

@@ -51,10 +51,10 @@ jobs:
 
 
       - name: Install R
-        uses: r-lib/actions/setup-r@v2.8.7
+        uses: r-lib/actions/setup-r@v2.9.0
 
       - name: Install R dependencies
-        uses: r-lib/actions/setup-r-dependencies@v2.8.7
+        uses: r-lib/actions/setup-r-dependencies@v2.9.0
         with:
           packages: |
             any::roxygen2

.github/workflows/main.yaml

@@ -192,10 +192,10 @@ jobs:
           submodules: recursive
 
       - name: Install R
-        uses: r-lib/actions/setup-r@v2.8.7
+        uses: r-lib/actions/setup-r@v2.9.0
 
       - name: Install R dependencies
-        uses: r-lib/actions/setup-r-dependencies@v2.8.7
+        uses: r-lib/actions/setup-r-dependencies@v2.9.0
         with:
           packages: |
             any::R6