Make release creation instructions more robust

The change fixes this error:

```
$ git fetch --tags && \
git tag -l | sort -V
remote: Enumerating objects: 4, done.
remote: Counting objects: 100% (2/2), done.
remote: Total 4 (delta 2), reused 2 (delta 2), pack-reused 2 (from 1)
Unpacking objects: 100% (4/4), 1.75 KiB | 12.00 KiB/s, done.
From https://github.com/commontk/AppLauncher
 * [new tag]         v0.1.33    -> v0.1.33
 ! [rejected]        v0.1.34    -> v0.1.34  (would clobber existing tag)
```

Author: lassoan

README.md

@@ -375,14 +375,14 @@ See [CONTRIBUTING.md][contributing] for more details.
 <details>
 <summary>click to expand</summary>
 
-1. List all tags sorted by version
+1. List all tags sorted by version (overwrites any local tags)
 
     ```bash
-    git fetch --tags && \
+    git fetch --tags -f && \
     git tag -l | sort -V
     ```
 
-2. Choose the next release version number (without
+2. Choose the next release version number
 
     ```bash
     tag=vX.Y.Z