set version via gha

.github/workflows/up.yml

@@ -0,0 +1,20 @@
+---
+name: up
+on:
+  push:
+jobs:
+  up:
+    runs-on: ubuntu-20.04
+    steps:
+      - uses: actions/checkout@v3
+      - run: |-
+          git pull --tags && \
+          latest=$(git tag | grep ^0 | tail -1) && \
+          sed -E -i "s/<version>[^<]+/<version>${latest}/g" README.md && \
+          sed -E -i "s/org.cactoos:cactoos:.+/org.cactoos:cactoos::${latest}/g" README.md
+      - uses: peter-evans/create-pull-request@v5
+        with:
+          commit-message: 'new version in README'
+          delete-branch: true
+          title: 'New version in README'
+          assignees: yegor256

README.md

@@ -41,17 +41,20 @@ The library has no dependencies. All you need is this
 (get the latest version [here](https://github.com/yegor256/cactoos/releases)):
 
 Maven:
+
 ```xml
 <dependency>
   <groupId>org.cactoos</groupId>
   <artifactId>cactoos</artifactId>
+  <version>0.0.0</version>
 </dependency>
 ```
 
 Gradle:
+
 ```groovy
 dependencies {
-    compile 'org.cactoos:cactoos:<version>'
+  compile 'org.cactoos:cactoos:0.0.0'
 }
 ```