Fix indentation in templates

Use Jinja2 lstrip_blocks option in templates to ensure consistent
indentation in generated files.

roles/matrix-postgres/templates/usr-local-bin/matrix-make-user-admin.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 #!/bin/bash
 
 if [ $# -ne 1 ]; then

roles/matrix-postgres/templates/usr-local-bin/matrix-postgres-cli.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 #!/bin/bash
 
 docker run \

roles/matrix-postgres/templates/usr-local-bin/matrix-postgres-update-user-password-hash.j2

@@ -1,3 +1,4 @@
+#jinja2: lstrip_blocks: "True"
 #!/bin/bash
 
 if [ $# -ne 2 ]; then