Switch action build to ESM for exec v3

Move from CJS to ESM because @actions/exec v3 is ESM‑only and fails to
bundle under ncc CJS output. Marking the package as ESM lets ncc emit ESM
bundles that Node >=20 is able to run in GitHub Actions.

Also renaming the eslint config file to .cjs as adding "type": "module"
makes Node treat .js files as ESM, so ESLint can't require() .eslintrc.js
unless it’s renamed to .cjs.

Author: dbast

.eslintrc.js .eslintrc.cjs.eslintrc.js renamed to .eslintrc.cjs

@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}

dist/delete/index.js

@@ -0,0 +1,3 @@
+{
+  "type": "module"
+}

dist/delete/package.json

@@ -1,6 +1,7 @@
 {
   "name": "setup-miniconda",
   "description": "GitHub action for setting up conda from default or custom installers",
+  "type": "module",
   "main": "lib/main.js",
   "scripts": {
     "build": "ncc build -o dist/setup src/setup.ts && ncc build -o dist/delete src/delete.ts",

dist/setup/index.js

@@ -1,3 +1,3 @@
 {
-  "include": [".eslintrc.js"]
+  "include": [".eslintrc.cjs"]
 }

dist/setup/package.json

@@ -4,8 +4,8 @@
     "allowSyntheticDefaultImports": true,
     "declaration": false,
     "esModuleInterop": true,
-    "module": "commonjs",
-    "moduleResolution": "node",
+    "module": "esnext",
+    "moduleResolution": "bundler",
     "noEmitOnError": true,
     "noImplicitAny": true,
     "noUnusedLocals": true,