Merge pull request #341 from kenjis/update-docs

docs: small update

Author: kenjis

README.md

@@ -62,7 +62,7 @@ Every open-source project depends on it's contributors to be a success. The foll
 contributed in one manner or another in making Shield:
 
 <a href="https://github.com/codeigniter4/shield/graphs/contributors">
-  <img src="https://contrib.rocks/image?repo=codeigniter4/shield" />
+  <img src="https://contrib.rocks/image?repo=codeigniter4/shield" alt="Contributors">
 </a>
 
 Made with [contrib.rocks](https://contrib.rocks).

docs/install.md

@@ -73,6 +73,10 @@ When you run `spark migrate --all`, if you get `Class "SQLite3" not found` error
 1. Remove sample migration files in `tests/_support/Database/Migrations/`
 2. Or install `sqlite3` php extension
 
+If you get `Specified key was too long` error:
+
+1. Use InnoDB, not MyISAM.
+
 ---
 
 ## Initial Setup