Update Composer, update everything

vendor/consolidation/self-update/README.md

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+# SelfUpdate
+
+Symfony Console command to update a phar in place.
+
+## Usage
+
+To use the self:update command, instantiate it with the name of the application,
+its current version, and the full name of the GitHub project.
+```
+$cmd = new SelfUpdateCommand('MyAppName', '1.0.0', 'org/my-app');
+$app->add($cmd);
+```
+
+## Similar Projects
+
+- https://github.com/DavaHome/self-update
+- https://github.com/padraic/phar-updater