Simplify workflow setup and update README

Updating workflow and README, all packages we need are available from
apt sources, skipping both pip and gem.

Supplement instructions in README and mention shortcut on Debian/Ubuntu.

Signed-off-by: Joachim Wiberg <[email protected]>

Author: troglobit

.github/workflows/main.yml

@@ -17,18 +17,12 @@ jobs:
       with:
         python-version: '3.x'
 
-    - name: Install pip
-      run: |
-        python -m pip install --upgrade pip
-
     - name: Install dependencies
       run: |
         sudo apt-get update
-        sudo apt-get install -y tcl tcllib expect ruby ruby-dev build-essential
-        pip install pyyaml
-        gem install --user-install asciidoctor-pdf
-        gem install --user-install rouge
-        echo "PATH=$PATH:$(ruby -e 'puts Gem.user_dir')/bin" >> $GITHUB_ENV
+        sudo apt-get install -y tcl tcllib expect ruby ruby-dev \
+             build-essential python3-yaml python3-slugify       \
+             ruby-asciidoctor-pdf ruby-rouge
 
     - name: Run Self Tests
       run: make check

README.md

@@ -27,8 +27,13 @@
 2. Install dependencies:
    ```bash
    pip install pyyaml
+   gem install --user-install asciidoctor-pdf rouge
    ```
 
+> [!NOTE]
+> On Debian/Ubuntu systems you can use standard packages for the requirements:
+> `sudo apt install python3-yaml ruby-asciidoctor-pdf ruby-rouge`
+
 ---
 
 ## Usage