Update scanner.odin

remove duplicated wording in comment

core/text/scanner/scanner.odin

@@ -2,7 +2,7 @@
 // It takes a string providing the source, which then can be tokenized through
 // repeated calls to the scan procedure.
 // For compatibility with existing tooling and languages, the NUL character is not allowed.
-// If an UTF-8 encoded byte order mark (BOM) is the first character in the first character in the source, it will be discarded.
+// If an UTF-8 encoded byte order mark (BOM) is the first character in the source, it will be discarded.
 //
 // By default, a Scanner skips white space and Odin comments and recognizes all literals defined by the Odin programming language specification.
 // A Scanner may be customized to recognize only a subset of those literals and to recognize different identifiers and white space characters.