wgsl: Fix capitalization of section headers (gpuweb#3817)

wgsl/index.bs

@@ -547,7 +547,7 @@ A [=shader-creation error=] results if:
 * the entire source text cannot be converted into a finite sequence of valid tokens, or
 * the [=syntax/translation_unit=] grammar rule does not match the entire token sequence.
 
-## Blankspace and line breaks ## {#blankspace-and-line-breaks}
+## Blankspace and Line Breaks ## {#blankspace-and-line-breaks}
 
 <dfn>Blankspace</dfn> is any combination of one or more of code points from the Unicode
 [=Unicode Standard Annex #31 for Unicode Version 14.0.0|Pattern_White_Space=] property.
@@ -15263,7 +15263,7 @@ Use token definitions from the main part of the specification.
 path: wgsl.recursive.bs.include
 </pre>
 
-# Appendix A: The `text/wgsl` media type # {#text-wgsl-media-type}
+# Appendix A: The `text/wgsl` Media Type # {#text-wgsl-media-type}
 
 The Internet Assigned Numbers Authority (IANA) maintains a registry of media types, at [[IANA-MEDIA-TYPES]].