get method from transaction read function should accept Query type

[sushantdhiman]

This concern was earlier raised in #6, but was lost in discussion.

For Node.js SDK
Transaction support reading multiple documents using get by passing Query.

https://github.com/googleapis/nodejs-firestore/blob/f5bec38de92479ca7930178089843e77411ead3d/types/firestore.d.ts#L450-L457

For Firestore JS SDK
I don't think this is supported for Web version.

https://firebase.google.com/docs/reference/js/firebase.firestore.Transaction#get

Current v8 implementation for this library still only supports getting single reference in transaction read function. get should accept Query as well, so it can read multiple documents and acquire pessimistic lock on them.

[kossnocorp]

Fixed with v10