clippy: fix byte_char_slices lint

https://rust-lang.github.io/rust-clippy/master/index.html#byte_char_slices

Author: xtqqczze

tests/by-util/test_env.rs

@@ -1707,8 +1707,8 @@ mod test_raw_string_parser {
             let mut buffer = [0u8; 4];
             let owl = '🦉'.encode_utf8(&mut buffer);
             owl_invalid_part = owl.bytes().next().unwrap();
-            brace_1 = [b'<'].to_vec();
-            brace_2 = [b'>'].to_vec();
+            brace_1 = b"<".to_vec();
+            brace_2 = b">".to_vec();
         }
         let mut input_ux = brace_1;
         input_ux.push(owl_invalid_part);

tests/by-util/test_numfmt.rs

@@ -1507,7 +1507,7 @@ fn test_format_precision_zero_with_to_scale_issue_11667() {
 fn test_invalid_utf8_input() {
     // 0xFF is invalid UTF-8
     new_ucmd!()
-        .pipe_in([b'1', b'0', b'\n', b'\xFF'])
+        .pipe_in(*b"10\n\xFF")
         .fails_with_code(2)
         .stdout_is("10\n")
         .stderr_is("numfmt: invalid number: '\\377'\n");

tests/by-util/test_tr.rs

@@ -75,34 +75,34 @@ fn test_delete() {
 
 #[test]
 fn test_delete_graph_and_print_match_gnu() {
-    let input = [b' ', b'A', b'!', b'\t', b'\n'];
+    let input = *b" A!\t\n";
     new_ucmd!()
         .args(&["-d", "[:graph:]"])
         .pipe_in(input)
         .succeeds()
-        .stdout_is_bytes([b' ', b'\t', b'\n']);
+        .stdout_is_bytes(*b" \t\n");
 
     new_ucmd!()
         .args(&["-d", "[:print:]"])
         .pipe_in(input)
         .succeeds()
-        .stdout_is_bytes([b'\t', b'\n']);
+        .stdout_is_bytes(*b"\t\n");
 }
 
 #[test]
 fn test_delete_complement_graph_and_print_match_gnu() {
-    let input = [b' ', b'A', b'!', b'\t', b'\n'];
+    let input = *b" A!\t\n";
     new_ucmd!()
         .args(&["-d", "-c", "[:graph:]"])
         .pipe_in(input)
         .succeeds()
-        .stdout_is_bytes([b'A', b'!']);
+        .stdout_is_bytes(*b"A!");
 
     new_ucmd!()
         .args(&["-d", "-c", "[:print:]"])
         .pipe_in(input)
         .succeeds()
-        .stdout_is_bytes([b' ', b'A', b'!']);
+        .stdout_is_bytes(*b" A!");
 }
 
 #[test]