Partially automate release - release branch creation and version updates [DI-669]

_Partially_ automates the steps listed in [the `C++ Client Release Process` documentation](https://hazelcast.atlassian.net/wiki/spaces/HZC/pages/129810774/C+Client+Release+Process).

Specifically, steps:
- `Create branch`
- `Update next version`

By scripting and chaining the steps, the (manual) release work is reduced and consistency is improved.

Testing (in my fork):
- [example execution](https://github.com/JackPGreen/hazelcast-cpp-client/actions/runs/19166496611)
- [branch created](https://github.com/JackPGreen/hazelcast-cpp-client/tree/5.5.0)
- [version update PR raised](JackPGreen#5)

Post-merge actions:
- [ ] update docs

_Partially addresses_: [DI-669](https://hazelcast.atlassian.net/browse/DI-669)

Author: JackPGreen

.github/workflows/update-versions.yml

@@ -0,0 +1,68 @@
+name: Create release branch
+
+on:
+  workflow_dispatch:
+    inputs:
+      BRANCH_NAME:
+        description: The source branch to work with, if not implicit
+        required: false
+      NEW_VERSION:
+        description: New version to set in the source branch (e.g. 5.6.0)
+        required: true
+
+jobs:
+  prepare:
+    name: Prepare
+    runs-on: ubuntu-latest
+    outputs:
+      branch_name: ${{ inputs.BRANCH_NAME || github.ref_name }}
+    steps:
+      - run: exit 0
+
+  make-branch:
+    name: Make branch
+    runs-on: ubuntu-latest
+    needs:
+      - prepare
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          ref: ${{ needs.prepare.outputs.branch_name }}
+
+      - name: Determine project version
+        id: project_version
+        run: |
+          echo "version=$(jq --raw-output '.version' vcpkg.json)" >> ${GITHUB_OUTPUT}
+
+      - name: Create `${{ steps.project_version.outputs.version }}` branch
+        run: |
+          git checkout -b ${{ steps.project_version.outputs.version }}
+          git push origin ${{ steps.project_version.outputs.version }}
+
+  update-version:
+    name: Update version in `${{ needs.prepare.outputs.branch_name }}` to `${{ inputs.NEW_VERSION }}`
+    runs-on: ubuntu-latest
+    needs:
+      - prepare
+    env:
+        NEW_VERSION: ${{ inputs.NEW_VERSION }}
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          ref: ${{ needs.prepare.outputs.branch_name }}
+
+      - name: Update `vcpkg.json`
+        run: |
+            cat <<< $(jq --arg ver "${NEW_VERSION}" '.version = $ver' vcpkg.json) > vcpkg.json
+
+      - name: Update `CMakeLists.txt`s
+        run: |
+            find . -name 'CMakeLists.txt' | \
+                xargs perl -0777 -i -pe 's/(project\s*\([^)]*?\bVERSION\s+)\S+/\1$ENV{NEW_VERSION}/s'
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v7
+        with:
+          branch: Update_version_to_${{ inputs.NEW_VERSION }}_run_${{ github.run_id }}
+          title: Update development version to `${{ inputs.NEW_VERSION }}`
+          body: ""