Normalize suffix capitalization

The grammar almost always uses lowercase, so let's standardize on that.

Author: ehuss

src/identifiers.md

@@ -7,9 +7,9 @@ r[ident.syntax]
 > &nbsp;&nbsp; &nbsp;&nbsp; XID_Start XID_Continue<sup>\*</sup>\
 > &nbsp;&nbsp; | `_` XID_Continue<sup>+</sup>
 >
-> RAW_IDENTIFIER : `r#` IDENTIFIER_OR_KEYWORD <sub>*Except `crate`, `self`, `super`, `Self`*</sub>
+> RAW_IDENTIFIER : `r#` IDENTIFIER_OR_KEYWORD <sub>*except `crate`, `self`, `super`, `Self`*</sub>
 >
-> NON_KEYWORD_IDENTIFIER : IDENTIFIER_OR_KEYWORD <sub>*Except a [strict] or [reserved] keyword*</sub>
+> NON_KEYWORD_IDENTIFIER : IDENTIFIER_OR_KEYWORD <sub>*except a [strict] or [reserved] keyword*</sub>
 >
 > IDENTIFIER :\
 > NON_KEYWORD_IDENTIFIER | RAW_IDENTIFIER

src/tokens.md

@@ -750,7 +750,7 @@ r[lex.token.life.syntax]
 >    | RAW_LIFETIME
 >
 > RAW_LIFETIME :\
-> &nbsp;&nbsp; `'r#` [IDENTIFIER_OR_KEYWORD][identifier] <sub>*Except `crate`, `self`, `super`, `Self`*</sub>
+> &nbsp;&nbsp; `'r#` [IDENTIFIER_OR_KEYWORD][identifier] <sub>*except `crate`, `self`, `super`, `Self`*</sub>
 >   _(not immediately followed by `'`)_
 >
 > RESERVED_RAW_LIFETIME : `'r#_`
@@ -849,10 +849,10 @@ r[lex.token.reserved-prefix]
 
 r[lex.token.reserved-prefix.syntax]
 > **<sup>Lexer 2021+</sup>**\
-> RESERVED_TOKEN_DOUBLE_QUOTE : ( IDENTIFIER_OR_KEYWORD <sub>_Except `b` or `c` or `r` or `br` or `cr`_</sub> | `_` ) `"`\
-> RESERVED_TOKEN_SINGLE_QUOTE : ( IDENTIFIER_OR_KEYWORD <sub>_Except `b`_</sub> | `_` ) `'`\
-> RESERVED_TOKEN_POUND : ( IDENTIFIER_OR_KEYWORD <sub>_Except `r` or `br` or `cr`_</sub> | `_` ) `#`\
-> RESERVED_TOKEN_LIFETIME : `'` (IDENTIFIER_OR_KEYWORD <sub>_Except `r`_</sub> | _) `#`
+> RESERVED_TOKEN_DOUBLE_QUOTE : ( IDENTIFIER_OR_KEYWORD <sub>_except `b` or `c` or `r` or `br` or `cr`_</sub> | `_` ) `"`\
+> RESERVED_TOKEN_SINGLE_QUOTE : ( IDENTIFIER_OR_KEYWORD <sub>_except `b`_</sub> | `_` ) `'`\
+> RESERVED_TOKEN_POUND : ( IDENTIFIER_OR_KEYWORD <sub>_except `r` or `br` or `cr`_</sub> | `_` ) `#`\
+> RESERVED_TOKEN_LIFETIME : `'` ( IDENTIFIER_OR_KEYWORD <sub>_except `r`_</sub> | `_` ) `#`
 
 r[lex.token.reserved-prefix.intro]
 Some lexical forms known as _reserved prefixes_ are reserved for future use.