Update cheatsheets

tldr/mysql_secure_installation

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+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# mysql_secure_installation
+
+> Set up MySQL to have better security.
+> More information: <https://dev.mysql.com/doc/refman/en/mysql-secure-installation.html>.
+
+- Start an interactive setup:
+
+`mysql_secure_installation`
+
+- Use specific host and port:
+
+`mysql_secure_installation --host={{host}} --port={{port}}`
+
+- Display help:
+
+`mysql_secure_installation --help`