[Snyk] Security upgrade @google-cloud/firestore from 0.15.2 to 0.21.0#6

Open

snyk-bot wants to merge 1 commit intomasterfrom

snyk-fix-e5de2d8f4f4cdf34ebe2137dce02481d

Commits on Dec 24, 2020

fix: package.json & package-lock.json to reduce vulnerabilities
snyk-bot
committed