sync-templates: enable syncing from stable release patches (#7227)

# Description

We're unable to sync templates repos with what's in
polkadot-sdk/templates for stable2412 because the tag which references
the release (`polkadot-stable2412`) is missing the Plan.toml file, which
is needed by PSVM, ran when syncing, to update the templates
dependencies versions in Cargo.tomls. This PR adds a workflow `patch`
input, to enable the workflow to use PSVM with a tag corresponding to a
patch stable release (e.g. `polkadot-stable2412-1`), which will contain
the `Plan.toml` file.

## Integration

This enables the templates repos update with the contents of latest
stable2412 release, in terms of polkadot-sdk/templates, which is
relevant for getting-started docs.

## Review Notes

This PR adds a `patch` input for the `misc-sync-templates.yml` workflow,
which if set will be used with `psvm` accordingly to update templates
repos' dependencies versions based on upcomming patch stable2412-1,
which contains the `Plan.toml`. The workflow will be ran manually after
stable2412-1 is out and this work is tracked under #6329 .

Signed-off-by: Iulian Barbu <iulian.barbu@parity.io>

.github/workflows/misc-sync-templates.yml

@@ -25,6 +25,10 @@ on:
         description: Enable runner debug logging
         required: false
         default: false
+      patch:
+        description: 'Patch number of the stable release we want to sync with'
+        required: false
+        default: ""
 
 jobs:
   sync-templates:
@@ -139,7 +143,14 @@ jobs:
           rm -f "${{ env.template-path }}/src/lib.rs"
 
       - name: Run psvm on monorepo workspace dependencies
-        run: psvm -o -v ${{ github.event.inputs.stable_release_branch }} -p ./Cargo.toml
+        run: |
+          patch_input="${{ github.event.inputs.patch }}"
+          if [[ -n "$patch_input" ]]; then
+            patch="-$patch_input"
+          else
+            patch=""
+          fi
+          psvm -o -v "${{ github.event.inputs.stable_release_branch }}$patch" -p ./Cargo.toml
         working-directory: polkadot-sdk/
       - name: Copy over required workspace dependencies
         run: |