Add eslint-plugin-github and fix issues (#29201)

This plugin has a few useful rules. The only thing I dislike about it is
that it pulls in a rather big number of dependencies for react-related
rules we don't use, but it can't really be avoided.

Rule docs:
https://github.com/github/eslint-plugin-github?tab=readme-ov-file#rules

build/generate-images.js

@@ -79,4 +79,8 @@ async function main() {
   ]);
 }
 
-main().then(exit).catch(exit);
+try {
+  exit(await main());
+} catch (err) {
+  exit(err);
+}

build/generate-svg.js

@@ -63,4 +63,8 @@ async function main() {
   ]);
 }
 
-main().then(exit).catch(exit);
+try {
+  exit(await main());
+} catch (err) {
+  exit(err);
+}