[charconv.to.chars, charconv.from.chars] Replace 'minus sign' with '-' (#1862)

Author: jensmaurer

source/utilities.tex

@@ -19583,7 +19583,7 @@
 Digits in the range 10..35 (inclusive)
 are represented as lowercase characters \tcode{a}..\tcode{z}.
 If \tcode{value} is less than zero,
-the representation starts with a minus sign.
+the representation starts with \tcode{'-'}.
 
 \pnum
 \throws Nothing.
@@ -19717,7 +19717,7 @@
 as described for \tcode{strtol},
 except that no \tcode{"0x"} or \tcode{"0X"} prefix shall appear
 if the value of \tcode{base} is 16,
-and except that a minus sign
+and except that \tcode{'-'}
 is the only sign that may appear,
 and only if \tcode{value} has a signed type.
 
@@ -19754,7 +19754,7 @@
 except that
 \begin{itemize}
 \item
-the only sign that may appear is a minus sign;
+the only sign that may appear is \tcode{'-'};
 \item
 if \tcode{fmt} has \tcode{chars_format::scientific} set
 but not \tcode{chars_format::fixed},