man: use tabs instead of spaces (fixes build)

otherwise sc-doc errors:
> FAILED: man/unl0kr.1
> meson --internal exe --capture man/unl0kr.1 --feed ../man/unl0kr.1.scd -- scdoc
> --- stderr ---
> Error at 48:1: Tabs are required for indentation

man/unl0kr.1.scd

@@ -45,7 +45,7 @@ password is printed to STDOUT. All other output happens on STDERR.
 *-h, --help*
 	Print this message and exit.
 *-n*
-        Do not append a newline character to a password.
+	Do not append a newline character to a password.
 *-v, --verbose*
 	Enable more detailed logging output on STDERR.
 *-V, --version*