fix conflict between filesize and hexadecimal numbers (#9309)

closes #9278 

# Description

removes ambiguity between the `b` the filesize `bytes` unit and `b` the
hex digit

src/tests/test_parser.rs

@@ -561,3 +561,8 @@ fn filesize_with_underscores_2() -> TestResult {
 fn filesize_with_underscores_3() -> TestResult {
     fail_test("42m_b", "executable was not found")
 }
+
+#[test]
+fn filesize_is_not_hex() -> TestResult {
+    run_test("0x42b", "1067")
+}