chore: Install plugin dev dependencies during workflow

This updates the automated generation for github workflows
to (also) install the dev dependencies for plugins.

This should resolve issues with workflows failing.
Or at the very least bring us closer to them working.

Shout-out to Jason for the peer pressure :)

config/templates/workflows/tests.plugin.yml

@@ -37,7 +37,7 @@ jobs:
         env:
           CI: true
       - name: Install peer & test dependencies
-        run: "cd packages/{{ plugin }} && npm install {{{ peerdeps }}} mocha chai"
+        run: "cd packages/{{ plugin }} && npm install {{{ peerdeps }}} {{{ devdeps }}}"
         env:
           CI: true
       - name: Build plugin

scripts/reconfigure.js

@@ -462,6 +462,7 @@ function configurePkgUnitTests(type, pkg, config) {
   const source = path.join(config.repoPath, 'config', 'templates', 'tests', `${type}s`)
   // Write templates
   const peerdeps = peerDependencies(pkg, config, type)
+  const devdeps = devDependencies(pkg, config, type)
   const replace = (type === 'pattern')
     ? {
         version,
@@ -472,9 +473,15 @@ function configurePkgUnitTests(type, pkg, config) {
           .join(' ')
       }
     : {
-      version,
+        version,
-      plugin: pkg,
+        plugin: pkg,
-      Plugin: capitalize(pkg),
+        Plugin: capitalize(pkg),
+        peerdeps: Object.keys(peerdeps)
+          .map((dep) => dep + '@' + peerdeps[dep])
+          .join(' '),
+        devdeps: Object.keys(devdeps)
+          .map((dep) => dep + '@' + devdeps[dep])
+          .join(' ')
     }
 
   for (const file of ['shared.test.mjs']) {