Remove unnecessary context from some util functions.

src/parser/comment.rs

@@ -55,7 +55,7 @@ fn comment_line<'r, 's>(
     context: Context<'r, 's>,
     input: OrgSource<'s>,
 ) -> Res<OrgSource<'s>, OrgSource<'s>> {
-    start_of_line(context, input)?;
+    start_of_line(input)?;
     let (remaining, _indent) = space0(input)?;
     let (remaining, (_hash, _leading_whitespace_and_content, _line_ending)) = tuple((
         tag("#"),