DEV: Remove rfc176-shims

Ember has now migrated to the new module layout, so these shims are no longer required

app/assets/javascripts/discourse/lib/rfc176-shims/.npmrc

@@ -1 +0,0 @@
-engine-strict = true

app/assets/javascripts/discourse/lib/rfc176-shims/index.js

@@ -1,61 +0,0 @@
-"use strict";
-
-// In core, babel-plugin-ember-modules-api-polyfill takes care of re-writing the new module
-// syntax to the legacy Ember globals. For themes and plugins, we need to manually set up
-// the modules.
-//
-// Eventually, Ember RFC176 will be implemented, and we can drop these shims.
-
-const RFC176Data = require("ember-rfc176-data");
-
-module.exports = {
-  name: require("./package").name,
-
-  isDevelopingAddon() {
-    return true;
-  },
-
-  contentFor: function (type) {
-    if (type !== "vendor-suffix") {
-      return;
-    }
-
-    const modules = {};
-
-    for (const entry of RFC176Data) {
-      // Entries look like:
-      // {
-      //   global: 'Ember.expandProperties',
-      //   module: '@ember/object/computed',
-      //   export: 'expandProperties',
-      //   deprecated: false
-      // },
-
-      if (entry.deprecated) {
-        continue;
-      }
-
-      let m = modules[entry.module];
-      if (!m) {
-        m = modules[entry.module] = [];
-      }
-
-      if (entry.module === "@ember/test") {
-        m.push({ ...entry, global: `(Ember.Test && ${entry.global})` });
-      } else {
-        m.push(entry);
-      }
-    }
-
-    let output = "";
-    for (const moduleName of Object.keys(modules)) {
-      const exports = modules[moduleName];
-      const rawExports = exports
-        .map((e) => `${e.export}:${e.global}`)
-        .join(",");
-      output += `define("${moduleName}", () => {return {${rawExports}}});\n`;
-    }
-
-    return output;
-  },
-};

app/assets/javascripts/discourse/lib/rfc176-shims/package.json

@@ -1,6 +0,0 @@
-{
-  "name": "rfc176-shims",
-  "keywords": [
-    "ember-addon"
-  ]
-}

app/assets/javascripts/discourse/package.json

@@ -89,8 +89,7 @@
   },
   "ember-addon": {
     "paths": [
-      "lib/bootstrap-json",
-      "lib/rfc176-shims"
+      "lib/bootstrap-json"
     ]
   },
   "devDependencies": {