build: fix wakatime json import bug (#2050)

* build: fix vercel node version

* build: remove engine property

* fix: add json import workarround

This commit adds a workaround for importing the `languageColors` JSON
file. This needed to be done since Vercel uses v16.4, which does not
support JSON file importing without the `experimental-json-modules`
flag. See https://simonplend.com/import-json-in-es-modules/
for more information. The workaround can be found [here](https://stackoverflow.com/questions/66726365/how-should-i-import-json-in-node).

package-lock.json

@@ -32,9 +32,6 @@
         "lodash.snakecase": "^4.1.1",
         "parse-diff": "^0.7.0",
         "prettier": "^2.1.2"
-      },
-      "engines": {
-        "node": ">=13"
       }
     },
     "node_modules/@actions/core": {