composer: pin to v1

I don't "need" v2 at the moment, but have reasons to stick to v1 for
now: wikimedia/composer-merge-plugin#184

.bash_aliases

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 
-alias composer='echo "composer via docker via alias" && docker run -it --rm --user $(id -u):$(id -g) -v ~/.composer:/tmp -v $(pwd):/app docker.io/composer'
+alias composer='echo "composer via docker via alias" && docker run -it --rm --user $(id -u):$(id -g) -v ~/.composer:/tmp -v $(pwd):/app docker.io/composer:1'
 alias php='echo "PHP 7.2 via docker via alias" && docker run -it --rm --user $(id -u):$(id -g) -v $(pwd):/usr/src/myapp -w /usr/src/myapp php:7.2-cli'
 alias phpstan='echo "phpstan via docker via alias" && docker run -t --rm --user $(id -u):$(id -g) -v $(pwd):/app:ro phpstan/phpstan:0.8'
 alias ansible-lint='echo "ansible-lint via docker via alias" && docker run -t --rm --user $(id -u):$(id -g) -v $(pwd):/app:ro -v ~/.ansible:/.ansible -w /app particlekit/ansible-lint ansible-lint'