Chore: Upgrades jQuery and @types/jQuery (#25651)

* Chore: upgrades jQuery and @types/jQuery

* Chore: reduce strict null errors

* Fixed issue in graphite func editor

Co-authored-by: Torkel Ödegaard <torkel@grafana.com>

package.json

@@ -84,7 +84,7 @@
     "@types/hoist-non-react-statics": "3.3.0",
     "@types/is-hotkey": "0.1.1",
     "@types/jest": "26.0.0",
-    "@types/jquery": "3.3.32",
+    "@types/jquery": "3.3.38",
     "@types/lodash": "4.14.149",
     "@types/lru-cache": "^5.1.0",
     "@types/marked": "0.6.5",
@@ -232,7 +232,7 @@
     "hoist-non-react-statics": "3.3.0",
     "immutable": "3.8.2",
     "is-hotkey": "0.1.6",
-    "jquery": "3.4.1",
+    "jquery": "3.5.1",
     "jsurl": "^0.1.5",
     "lodash": "4.17.15",
     "lru-cache": "^5.1.1",