remove trailing whitespace

doc/Language/modules.pod6

@@ -159,7 +159,7 @@ tags: C<ALL>, C<DEFAULT> and C<MANDATORY>.
     use MyModule :ALL;     # bag, pants, sunglasses, torch, underpants
     =end code
 
-Note there currently is no way for the user to import a single object if 
+Note there currently is no way for the user to import a single object if
 the module author hasn't made provision for that, and it is not an easy
 task at the moment (see RT #127305). One way the author can provide
 such access is to give each C<export> trait its own unique tag. (And the tag
@@ -168,7 +168,7 @@ can be the object name!) Then the user can either (1) import all objects:
     =begin code
     use Foo :ALL;
     =end code
-    
+
 or (2) import one or more objects selectively:
 
     =begin code
@@ -194,7 +194,7 @@ no matter whether the using program adds any tag or not.
 
 5. Multiple tags may be used in the C<export> trait, but they must
    all be separated by either commas, or whitespace, but not both.
-   
+
    =begin code
    sub foo() is export(:foo :s2 :net) {}
    sub bar() is export(:bar, :s3, :some) {}