Upgrade cypress to allow Firefox tests to proceed.

A change in a newer Firefox version prevents cypress from running, but
that was fixed in a newer cypress. This commit upgrades to that version
as a minimum.

Author: Fryguy

cypress/downloads/downloads.html

@@ -129,7 +129,7 @@
     "core-js": "~3.6.4",
     "core-js-compat": "~3.2.1",
     "css-loader": "~3.4.2",
-    "cypress": "12.17.1",
+    "cypress": "^13.7.1",
     "duplicate-package-checker-webpack-plugin": "~3.0.0",
     "enhanced-resolve": "~4.0.0",
     "enzyme": "^3.9.0",