Use one sentence per line in admin create docs

Unwraps a sentence that was split across two lines.

Signed-off-by: arhimede <julian@dotkernel.com>

Author: arhimede

docs/book/v7/commands/create-admin-account.md

@@ -42,8 +42,7 @@ If the submitted data is valid, the outputted response is:
 ```
 
 All four options are required.
-If any is missing or invalid, the command fails with the input filter's validation messages instead,
-one per line.
+If any is missing or invalid, the command fails with the input filter's validation messages instead, one per line.
 
 The new admin account is ready to use.