refactor: use _auth= when migrating npm tokens

lib/config/decrypt.js

@@ -19,7 +19,7 @@ function decryptConfig(config, privateKey) {
             logger.info(`Decrypted ${eKey}`);
             if (eKey === 'npmToken') {
               logger.info('Migrating npmToken to npmrc');
-              decryptedConfig.npmrc = `//registry.npmjs.org/:_authToken=${decryptedStr}\n`;
+              decryptedConfig.npmrc = `_auth=${decryptedStr}\n`;
             } else {
               decryptedConfig[eKey] = decryptedStr;
             }

lib/config/massage.js

@@ -22,7 +22,7 @@ function massageConfig(config) {
     if (allowedStrings.includes(key) && typeof val === 'string') {
       massagedConfig[key] = [val];
     } else if (key === 'npmToken' && val && val.length < 30) {
-      massagedConfig.npmrc = `//registry.npmjs.org/:_authToken=${val}\n`;
+      massagedConfig.npmrc = `_auth=${val}\n`;
       delete massagedConfig.npmToken;
     } else if (isObject(val)) {
       massagedConfig[key] = massageConfig(val);

test/config/__snapshots__/massage.spec.js.snap

@@ -2,7 +2,7 @@
 
 exports[`config/massage massageConfig massages npmToken 1`] = `
 Object {
-  "npmrc": "//registry.npmjs.org/:_authToken=some-token
+  "npmrc": "_auth=some-token
 ",
 }
 `;

test/config/decrypt.spec.js

@@ -57,7 +57,7 @@ describe('config/decrypt', () => {
       );
       expect(res.packageFiles[0].devDependencies.npmToken).not.toBeDefined();
       expect(res.packageFiles[0].devDependencies.npmrc).toEqual(
-        '//registry.npmjs.org/:_authToken=abcdef-ghijklm-nopqf-stuvwxyz\n'
+        '_auth=abcdef-ghijklm-nopqf-stuvwxyz\n'
       );
     });
   });