fix: Don't specify any jsxBracketSameLine parameter if none is specified (#430)

By removing the default value for jsx-bracket-same-line (which is just
  `undefined` anyway), no option value at all for jsxBracketSameLine will
  be generated if none is specified. Then if a recent version of prettier
  is in use for which that option is deprecated, it won't complain.

  Resolves #428.

Author: gwhitney

.all-contributorsrc

@@ -232,6 +232,15 @@
         "maintenance"
       ]
     },
+    {
+      "login": "gwhitney",
+      "name": "Glen Whitney",
+      "avatar_url": "https://avatars.githubusercontent.com/u/3825429?v=4",
+      "profile": "https://github.com/gwhitney",
+      "contributions": [
+        "maintenance"
+      ]
+    },
     {
       "login": "idahogurl",
       "name": "Rebecca Vest",

README.md

@@ -279,6 +279,7 @@ Thanks goes to these people ([emoji key][emojis]):
   <tr>
     <td align="center"><a href="https://github.com/sscaff1"><img src="https://avatars1.githubusercontent.com/u/1554424?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Steven Scaffidi</b></sub></a><br /><a href="https://github.com/prettier/prettier-eslint-cli/commits?author=sscaff1" title="Documentation">📖</a></td>
     <td align="center"><a href="http://danielwilhelmsen.com"><img src="https://avatars3.githubusercontent.com/u/1758049?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Daniel Wilhelmsen</b></sub></a><br /><a href="https://github.com/prettier/prettier-eslint-cli/commits?author=dpwilhelmsen" title="Code">💻</a> <a href="#maintenance-dpwilhelmsen" title="Maintenance">🚧</a></td>
+    <td align="center"><a href="https://github.com/gwhitney"><img src="https://avatars.githubusercontent.com/u/3825429?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Glen Whitney</b></sub></a><br /><a href="#maintenance-gwhitney" title="Maintenance">🚧</a></td>
     <td align="center"><a href="https://campcode.dev/"><img src="https://avatars.githubusercontent.com/u/10620169?v=4?s=100" width="100px;" alt=""/><br /><sub><b>Rebecca Vest</b></sub></a><br /><a href="https://github.com/prettier/prettier-eslint-cli/commits?author=idahogurl" title="Code">💻</a></td>
   </tr>
 </table>