MAINT: Update Node to 20 (#13)

This PR follows the instructions in the "DEVELOPING.md" document
to update Node to version 20. In addition, a few unrelated changes
have been made

    CI uses latest versions of GitHub actions
    latest version of EDM is tested (v 3.7.0)
    Example code in README is updated

    Update action versions in README example #11 )

Note that this PR makes a forward looking change to the documentation
- enthought/setup-edm-action@v3 is used, given that we should be
releasing a new version of the action after this PR is merged.

.github/workflows/ci.yml

@@ -9,10 +9,10 @@ jobs:
         os: [ubuntu-latest, macos-latest, windows-latest]
     runs-on: ${{ matrix.os }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Install EDM
         uses: ./
         with:
-          edm-version: 3.1.1
+          edm-version: 3.7.0
       - name: Show EDM versions
         run: edm versions

DEVELOPING.md

@@ -7,7 +7,7 @@ The steps follow closely [GitHub documentation on creating a JavaScript action](
 The requirements are:
 
 - Git
-- Node.js (version 16)
+- Node.js (version 20)
 
 ## Directory structure
 

README.md

@@ -13,24 +13,24 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v4
       - name: Cache EDM packages
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.cache
           key: ${{ runner.os }}--${{ hashFiles('requirements.txt') }}
       - name: Setup EDM
-        uses: enthought/setup-edm-action@v1
+        uses: enthought/setup-edm-action@v3
         with:
-          edm-version: 3.1.1
+          edm-version: 3.7.0
       - name: Install Python packages
         run: edm install -y typing
 ```
 
 ## Inputs
 
 - `edm-version`: (Required)
-  A string to specify the EDM version to be installed, e.g. '3.1.1'
+  A string to specify the EDM version to be installed, e.g. '3.7.0'
 - `download-directory`: (Optional)
   A string to specify the directory for storing the downloaded installer.
   Default to `~/.cache/download`, which is within the default cache folder

action.yml

@@ -26,5 +26,5 @@ inputs:
     default: ~/.cache/download
 
 runs:
-  using: 'node16'
+  using: 'node20'
   main: 'dist/index.js'