Don't use require() in ESM files (#12728)

* Update `yarn-plugin-conditions`

* Don't use `require()` in ESM files

packages/babel-core/src/config/helpers/escape-regexp.cjs

@@ -0,0 +1,5 @@
+"use strict";
+
+module.exports = process.env.BABEL_8_BREAKING
+  ? require("escape-string-regexp")
+  : require("lodash/escapeRegExp");

packages/babel-core/src/config/pattern-to-regex.js

@@ -1,9 +1,8 @@
 // @flow
 import path from "path";
 
-const escapeRegExp = process.env.BABEL_8_BREAKING
-  ? require("escape-string-regexp")
-  : require("lodash/escapeRegExp");
+// $FlowIgnore
+import escapeRegExp from "./helpers/escape-regexp";
 
 const sep = `\\${path.sep}`;
 const endSep = `(?:${sep}|$)`;
@@ -42,13 +41,11 @@ export default function pathToPattern(
         // *.ext matches a wildcard with an extension.
         if (part.indexOf("*.") === 0) {
           return (
-            // $FlowIgnore
             substitution + escapeRegExp(part.slice(1)) + (last ? endSep : sep)
           );
         }
 
         // Otherwise match the pattern text.
-        // $FlowIgnore
         return escapeRegExp(part) + (last ? endSep : sep);
       }),
     ].join(""),