all: remove explicit imports of TryFrom and TryInto

This is enabled by the changing the edition from 2018 to 2021

src/uu/dd/src/dd.rs

@@ -23,7 +23,6 @@ mod blocks;
 use blocks::conv_block_unblock_helper;
 
 use std::cmp;
-use std::convert::TryInto;
 use std::env;
 use std::fs::{File, OpenOptions};
 use std::io::{self, Read, Seek, Write};

src/uu/head/src/head.rs

@@ -6,7 +6,6 @@
 // spell-checker:ignore (vars) zlines BUFWRITER seekable
 
 use clap::{crate_version, Arg, ArgMatches, Command};
-use std::convert::{TryFrom, TryInto};
 use std::ffi::OsString;
 use std::io::{self, BufWriter, ErrorKind, Read, Seek, SeekFrom, Write};
 use uucore::display::Quotable;

src/uu/od/src/od.rs

@@ -29,7 +29,6 @@ mod prn_float;
 mod prn_int;
 
 use std::cmp;
-use std::convert::TryFrom;
 
 use crate::byteorder_io::*;
 use crate::formatteriteminfo::*;

src/uu/seq/src/numberparse.rs

@@ -3,7 +3,6 @@
 //!
 //! This module provides an implementation of [`FromStr`] for the
 //! [`PreciseNumber`] struct.
-use std::convert::TryInto;
 use std::str::FromStr;
 
 use bigdecimal::BigDecimal;

src/uu/sort/src/sort.rs

@@ -33,7 +33,6 @@ use numeric_str_cmp::{human_numeric_str_cmp, numeric_str_cmp, NumInfo, NumInfoPa
 use rand::{thread_rng, Rng};
 use rayon::prelude::*;
 use std::cmp::Ordering;
-use std::convert::TryFrom;
 use std::env;
 use std::error::Error;
 use std::ffi::{OsStr, OsString};

src/uu/split/src/split.rs

@@ -14,7 +14,6 @@ mod platform;
 use crate::filenames::FilenameIterator;
 use crate::filenames::SuffixType;
 use clap::{crate_version, Arg, ArgMatches, Command};
-use std::convert::TryInto;
 use std::env;
 use std::fmt;
 use std::fs::{metadata, File};

src/uu/stdbuf/src/stdbuf.rs

@@ -11,7 +11,6 @@
 extern crate uucore;
 
 use clap::{crate_version, Arg, ArgMatches, Command};
-use std::convert::{TryFrom, TryInto};
 use std::fs::File;
 use std::io::{self, Write};
 use std::os::unix::process::ExitStatusExt;

src/uu/tail/src/tail.rs

@@ -22,7 +22,6 @@ use chunks::ReverseChunks;
 
 use clap::{Arg, Command};
 use std::collections::VecDeque;
-use std::convert::TryInto;
 use std::ffi::OsString;
 use std::fmt;
 use std::fs::{File, Metadata};

src/uucore/src/lib/features/entries.rs

@@ -41,7 +41,6 @@ use libc::{c_char, c_int, gid_t, uid_t};
 use libc::{getgrgid, getgrnam, getgroups};
 use libc::{getpwnam, getpwuid, group, passwd};
 
-use std::convert::TryInto;
 use std::ffi::{CStr, CString};
 use std::io::Error as IOError;
 use std::io::ErrorKind;

src/uucore/src/lib/features/fs.rs

@@ -99,8 +99,6 @@ impl FileInformation {
     pub fn file_size(&self) -> u64 {
         #[cfg(unix)]
         {
-            use std::convert::TryInto;
-
             assert!(self.0.st_size >= 0, "File size is negative");
             self.0.st_size.try_into().unwrap()
         }

src/uucore/src/lib/parser/parse_size.rs

@@ -5,7 +5,6 @@
 
 // spell-checker:ignore (ToDO) hdsf ghead gtail
 
-use std::convert::TryFrom;
 use std::error::Error;
 use std::fmt;
 

tests/benches/factor/benches/table.rs

@@ -1,6 +1,5 @@
 use array_init::array_init;
 use criterion::{criterion_group, criterion_main, BenchmarkId, Criterion, Throughput};
-use std::convert::TryInto;
 use uu_factor::{table::*, Factors};
 
 fn table(c: &mut Criterion) {