Move filter and sort tests to pure tests

The filter and sort tests were located inside the React tests since they
were already using Jest. Now that the pure tests have been switched to
Jest, these tests can finally be moved to the "normal" pure tests.

extensions/ql-vscode/test/pure-tests/variant-analysis-filter-sort.test.ts

@@ -6,9 +6,8 @@ import {
   filterAndSortRepositoriesWithResultsByName,
   matchesFilter,
   SortKey,
-} from "../../../pure/variant-analysis-filter-sort";
+} from "../../src/pure/variant-analysis-filter-sort";
 
-// TODO: Move this file to the "pure" tests once it has been switched to Jest
 describe(matchesFilter.name, () => {
   const repository = {
     fullName: "github/codeql",