Allow to install TinyTeX in install-quarto action (#10)

Author: cderv

install-quarto/README.md

@@ -10,7 +10,9 @@ This action will:
 * On Windows, it will for now use **Scoop** (https://github.com/ScoopInstaller/Scoop) to install Quarto, as we have still an issue with Quarto MSI on Github Action (https://github.com/quarto-dev/quarto-cli/issues/108). (**Scoop** will be installed on the runner by the action)
 * On Linux and MacOS, it will use **gh** CLI to download the last available bundle (no `version` specified as input). If you don't have **gh** on your Github Action runner, you can specify a fix `version` to directly download from a URL using `wget`.
 
-Inputs available
+We recommend using this action on Linux or MacOS where it works best, especially if TinyTeX is needed.
+
+### Inputs available
 
 * `version` - _optional_. If provided, the specific quarto version will be installed. Ex: `version: 0.3.71`
 
@@ -21,7 +23,17 @@ Inputs available
           version: 0.3.71
   ```
 
-Example on different OS:
+* `tinytex` - _optional_. Set this to `tinytex: true` to let [Quarto installs TinyTeX](https://quarto.org/docs/output-formats/pdf-engine.html#installing-tex) using `quarto tools install tinytex`.  **Only available on `main` branch**  
+_Notice: Installing TinyTeX on Windows takes long time several minutes and will make your all job longer_
+
+  ```yaml
+    steps:
+      - uses: quarto-dev/quarto-actions/install-quarto@main
+        with:
+          tinytex: true
+  ```
+
+### Example on different OS
 
 ```yaml
 name: quarto-setup

install-quarto/action.yml

@@ -5,6 +5,10 @@ inputs:
   version:
     description: 'The version of Quarto CLI to install, as a release tag (https://github.com/quarto-dev/quarto-cli/releases). Ex: 0.3.73'
     required: false
+  tinytex:
+    description: 'Should TinyTex be installed for PDF rendering using TeX Live ?'
+    required: false
+    default: 'false'
 runs:
   using: 'composite'
   steps: 
@@ -72,3 +76,24 @@ runs:
         [ ${{ runner.os }} != "Windows" ] && rm $installer
         echo "Quarto Installed !"
       shell: bash
+    - name: Install TinyTeX
+      if: ${{ inputs.tinytex == 'true'}}
+      run: |
+        quarto tools install tinytex --log-level warning
+        case $RUNNER_OS in 
+          "Linux")
+              echo "$HOME/bin" >> $GITHUB_PATH
+              ;;
+           "macOS")
+              echo "$(dirname $(find ~/Library/TinyTeX -name tlmgr))" >> $GITHUB_PATH
+              ;;
+           "Windows")
+              echo "$(dirname $(find $APPDATA/TinyTeX -name tlmgr.bat))" >> $GITHUB_PATH
+              ;;
+            *)
+              echo "$RUNNER_OS not supported"
+              exit 1
+              ;;
+        esac
+        echo "TinyTeX installed !"
+      shell: bash