Correct scar path environment variable in scabbard man page
The man page said the variable was SCAR_PATH_ENV_VAR but it
is actually SCAR_PATH
@@ -70,7 +70,7 @@ ARGUMENTS
ENVIRONMENT VARIABLES
=====================
-**SCAR_PATH_ENV_VAR**
+**SCAR_PATH**
: List of directories to use when searching for the scar file to upload. (See
`-p`, `--path`.)
