Unit tests do not run against the emulator

[tsukasa-au]

Environment details

• OS type and version: Arch linux
• Python version: 3.8.2
• pip version: 20.0.2
• google-cloud-datastore version: master

Steps to reproduce

1. run unit tests

$(gcloud beta emulators datastore env-init)  # Enable the emulator
nox -s system-3.8  # Run test (using python3.8 support added in #31)

2. See failures where some tests run against the real datastore instance, others fail due to incorrect test data, while others fail due to bugs in the emulator.

[HemangChothani]

@tsukasa-au Python3.8 has added into the nox.py file so you can run system test against it. One error poped up when run against the emulator google.api_core.exceptions.ResourceExhausted: 429 Received message larger than max (28100227 vs. 4194304) because of the emulator limitation as you can see here, i will open an issue related to that and also you can find related opened issue in pubsub as well.

Closing the issue for now and Closing the FR as nox.py file changes is not valid. Feel free to reopen the issue if not satisfied.