Collection already exists error when applying script for mongo

## I'm submitting a...

- [x] Bug report
- [ ] Feature request
- [ ] Question

## Current behavior
I'm trying to do db-migrate scripts for a mongo instance.
I've created a really simple addIndex script as a test
I run db-migrate up, it creates the migrations collection, it adds the index but no records are added to the migrations collection. db-migrate doesn't know it's ran the script. Second time I run db-migrate up, an error is thrown stating that the collection already exists.

## Expected behavior
After running db-migrate up, the index is applied, the migrations collection is created with a document tracking what's been ran. The second time I run db-migrate up, nothing is applies since it's already been applied, and no errors occur.

## Minimal reproduction of the problem with instructions

## What is the motivation / use case for changing the behavior?
Can't use db-migration with mongo currently

## Environment

db-migrate version: 0.11.12

db-migrate driver with versions: mongodb v4.4.6


Others:

This is the error message:

[ERROR] AssertionError [ERR_ASSERTION]: ifError got unwanted exception: Collection already exists. NS: forms.migrations

    at module.exports (/Users/jselah/src/forms-user-service/migrate/node_modules/db-migrate/lib/commands/helper/assert.js:9:14)

    at /Users/jselah/src/forms-user-service/migrate/node_modules/db-migrate/lib/commands/up.js:29:16

    at tryCatcher (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/util.js:16:23)

    at Promise.errorAdapter [as _rejectionHandler0] (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/nodeify.js:35:34)

    at Promise._settlePromise (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/promise.js:601:21)

    at Promise._settlePromise0 (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/promise.js:649:10)

    at Promise._settlePromises (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/promise.js:725:18)

    at _drainQueueStep (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/async.js:93:12)

    at _drainQueue (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/async.js:86:9)

    at Async._drainQueues (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/async.js:102:5)

    at Immediate.Async.drainQueues [as _onImmediate] (/Users/jselah/src/forms-user-service/migrate/node_modules/bluebird/js/release/async.js:15:14)

    at processImmediate (node:internal/timers:463:21)

    at Connection. (/Users/jselah/src/forms-user-service/migrate/node_modules/db-migrate-mongodb-nesto-fork/node_modules/mongodb/lib/core/connection/pool.js:451:61)

    at Connection.emit (node:events:379:20)

    at processMessage (/Users/jselah/src/forms-user-service/migrate/node_modules/db-migrate-mongodb-nesto-fork/node_modules/mongodb/lib/core/connection/connection.js:451:10)

    at TLSSocket. (/Users/jselah/src/forms-user-service/migrate/node_modules/db-migrate-mongodb-nesto-fork/node_modules/mongodb/lib/core/connection/connection.js:620:15)

    at TLSSocket.emit (node:events:379:20)

    at addChunk (node:internal/streams/readable:313:12)

    at readableAddChunk (node:internal/streams/readable:288:9)

    at TLSSocket.Readable.push (node:internal/streams/readable:227:10)

    at TLSWrap.onStreamRead (node:internal/stream_base_commons:190:23)