feat(esm): convert to esm (#2569)

for #2543

BREAKING CHANGE: semantic-release is now ESM-only. since it is used through its own executable, the impact on consuming projects should be minimal

BREAKING CHANGE: references to plugin files in configs need to include the file extension because of executing in an ESM context

test/fixtures/index.js

@@ -1 +1 @@
-module.exports = () => {};
+export default () => {}

test/fixtures/plugin-error-inherited.js

@@ -1,4 +1,4 @@
-const SemanticReleaseError = require('@semantic-release/error');
+import SemanticReleaseError from '@semantic-release/error';
 
 class InheritedError extends SemanticReleaseError {
   constructor(message, code) {
@@ -9,6 +9,6 @@ class InheritedError extends SemanticReleaseError {
   }
 }
 
-module.exports = () => {
+export default () => {
   throw new InheritedError('Inherited error', 'EINHERITED');
-};
+}

test/fixtures/plugin-error.js

@@ -1,5 +1,5 @@
-module.exports = () => {
+export default () => {
   const error = new Error('a');
   error.errorProperty = 'errorProperty';
   throw error;
-};
+}

test/fixtures/plugin-errors.js

@@ -1,5 +1,5 @@
-const AggregateError = require('aggregate-error');
+import AggregateError from 'aggregate-error';
 
-module.exports = () => {
+export default () => {
   throw new AggregateError([new Error('a'), new Error('b')]);
-};
+}

test/fixtures/plugin-identity.js

@@ -1 +1 @@
-module.exports = (pluginConfig, context) => context;
+export default (pluginConfig, context) => context

test/fixtures/plugin-log-env.js

@@ -1,6 +1,6 @@
-module.exports = (pluginConfig, {env, logger}) => {
+export default (pluginConfig, {env, logger}) => {
   console.log(`Console: Exposing token ${env.MY_TOKEN}`);
   logger.log(`Log: Exposing token ${env.MY_TOKEN}`);
   logger.error(`Error: Console token ${env.MY_TOKEN}`);
   throw new Error(`Throw error: Exposing ${env.MY_TOKEN}`);
-};
+}

test/fixtures/plugin-result-config.js

@@ -1 +1 @@
-module.exports = (pluginConfig, context) => ({pluginConfig, context});
+export default (pluginConfig, context) => ({pluginConfig, context})