fixes asynchronous error with gitkeep, but do not process them

gulpfile.mjs

@@ -68,6 +68,7 @@ const convert = function (from, to, ofType, overwrite = true) {
             if (statSync(join(source, file)).isDirectory()) {
                 await filewalker(join(source, file))
             } else {
+                if (file.endsWith(".json")) {
                     console.debug("processing file", join(source, file))
                     let originalSource = JSON.parse(readFileSync(join(source, file), {encoding: "utf8"}))
                     promises.push(new Promise((resolve2) => {
@@ -94,6 +95,7 @@ const convert = function (from, to, ofType, overwrite = true) {
                 }
             }
         }
+    }
 
     filewalker(SOURCE)