"files.associations" does not override file icons defined in "fileExtensions"...

"files.associations" does not override file icons defined in "fileExtensions" or "fileNames" icon theme tables. Fixes #58366

extensions/theme-seti/build/update-icon-theme.js

@@ -309,6 +309,9 @@ exports.update = function () {
 					def2Content[def] = contents[match[2]];
 				}
 
+				if (def === '_default') {
+					continue; // no need to assign default color.
+				}
 				if (pattern[0] === '.') {
 					ext2Def[pattern.substr(1).toLowerCase()] = def;
 				} else {

extensions/theme-seti/icons/vs-seti-icon-theme.json

@@ -1349,7 +1349,6 @@
 		"sty": "_tex_1",
 		"dtx": "_tex_2",
 		"ins": "_tex_3",
-		"txt": "_default",
 		"toml": "_config",
 		"twig": "_twig",
 		"spec.ts": "_typescript_1",
@@ -1640,7 +1639,6 @@
 			"sty": "_tex_1_light",
 			"dtx": "_tex_2_light",
 			"ins": "_tex_3_light",
-			"txt": "_default_light",
 			"toml": "_config_light",
 			"twig": "_twig_light",
 			"spec.ts": "_typescript_1_light",