chore: Adds release-please workflow. (#105)

# What ❔

Adds release-please workflow triggered by push into main branch.
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## Why ❔

Preparing to use the repo for releases.
<!-- Why are these changes done? What goal do they contribute to? What
are the principles behind them? -->
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iterators are in context about the evolution of repos. -->

## Checklist

<!-- Check your PR fulfills the following items. -->
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- [x] PR title corresponds to the body of PR (we generate changelog
entries from PRs).
- [ ] Tests for the changes have been added / updated.
- [ ] Documentation comments have been added / updated.
- [ ] Code has been formatted via `zk fmt` and `zk lint`.

.github/release-please/config.json

@@ -0,0 +1,25 @@
+{
+  "separate-pull-requests": true,
+  "group-pull-request-title-pattern": "chore: release ${component} ${branch}",
+  "bootstrap-sha": "a980ac61f484a3b6bdbe11e606977d0d92d4e9ff",
+  "bump-minor-pre-major": true,
+  "bump-patch-for-minor-pre-major": true,
+  "packages": {
+      "core": {
+        "release-type": "simple",
+        "component": "core"
+      },
+      "sdk/zksync-web3.js": {
+        "release-type": "node",
+        "component": "web3js"
+      },
+      "sdk/zksync-rs": {
+        "release-type": "rust",
+        "component": "zksync-rs"
+      },
+      "prover": {
+        "release-type": "simple",
+        "component": "prover"
+      }
+  }
+}

.github/release-please/manifest.json

@@ -0,0 +1,6 @@
+{
+  "sdk/zksync-web3.js": "0.15.4",
+  "sdk/zksync-rs": "0.4.0",
+  "core": "15.0.1",
+  "prover": "7.1.1"
+}

.github/workflows/release-please.yml

@@ -0,0 +1,27 @@
+on:
+  push:
+    branches:
+      - main
+
+name: release-please
+jobs:
+  release-please:
+    runs-on: ubuntu-latest
+    outputs:
+      release_please_output: ${{ toJSON(steps.release.outputs) }}
+    steps:
+      - name: Run release-please
+        id: release
+        uses: google-github-actions/release-please-action@v3
+        with:
+            command: manifest
+            config-file: .github/release-please/config.json
+            manifest-file: .github/release-please/manifest.json
+            monorepo-tags: true
+
+      - name: Send Release Info
+        if: ${{ steps.release.outputs.releases_created }}
+        uses: matter-labs/format-release-please-for-slack-action@69e6fe9e4ec531b7b5fb0d826f73c190db83cf42 # v2.1.0
+        with:
+          release-please-output: ${{ toJSON(steps.release.outputs) }}
+          slack-webhook-url: ${{ secrets.SLACK_WEBHOOK_RELEASES }}