[clang-tidy] Don't split \r\n in modernize-use-std-print check

When given:
 printf("Hello\r\n");

it's clearer to leave the CRLF intact and convert this to:
 std::print("Hello\r\n");

than to remove the trailing newline and convert it to:
 std::println("Hello\r");

Update the documentation to match, and clarify the situations for using
println vs print which weren't previously explained.

Reviewed By: PiotrZSL

Differential Revision: https://reviews.llvm.org/D154788