@google-cloud/datastore version 7 support

[jacobg]

Thanks!

[dmk1111]

@jacobg starting from NodeJS v18 (npm v8) there is a possibility to override dependencies for other packages inside package.json.
Here is how I use overrides with @google-cloud/datastore@8.0.0:

"gstore-node@7.2.6": {
      "@google-cloud/datastore": "$@google-cloud/datastore"
    }