chore: added scripts/drop_compound_index.py

[viniarck]

Closes #160

I'll send a backport to 2022.3.2 shortly

Summary

See updated changelog for more information

Local Tests

• On version 2022.3.2 I ran this script:

❯ CMD=drop_index python3 drop_compound_index.py      
None

If you try to run again, it'll error out as expect since the index switch_1_flow.cookie_1_state_1_inserted_at_1_updated_at_1 doesn't exist anymore:

❯ CMD=drop_index python3 drop_compound_index.py
pymongo error: index not found with name [switch_1_flow.cookie_1_state_1_inserted_at_1_updated_at_1], full error: {'ok': 0.0, 'errmsg': 'index not found with name [switch_1_flow.cookie_1
_state_1_inserted_at_1_updated_at_1]', 'code': 27, 'codeName': 'IndexNotFound', '$clusterTime': {'clusterTime': Timestamp(1691420918, 2), 'signature': {'hash': b'\x00\x00\x00\x00\x00\x00
\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00', 'keyId': 0}}, 'operationTime': Timestamp(1691420918, 2)}

• On master (future 2023.1) I ran this script as well:

❯ CMD=drop_index python3 drop_compound_index.py      
None

rs0 [direct: primary] napps> db.flows.getIndexes()
[
  { v: 2, key: { _id: 1 }, name: '_id_' },
  {
    v: 2,
    key: { flow_id: 1 },
    name: 'flow_id_1',
    background: true,
    unique: true
  },
  {
    v: 2,
    key: { 'flow.cookie': 1 },
    name: 'flow.cookie_1',
    background: true
  },
  {
    v: 2,
    key: { 'flow.priority': -1 },
    name: 'flow.priority_-1',
    background: true
  },
  { v: 2, key: { state: 1 }, name: 'state_1', background: true },
  {
    v: 2,
    key: {
      switch: 1,
      'flow.cookie': 1,
      state: 1,
      'flow.priority': -1,
      inserted_at: 1,
      updated_at: 1
    },
    name: 'switch_1_flow.cookie_1_state_1_flow.priority_-1_inserted_at_1_updated_at_1',
    background: true
  }
]
rs0 [direct: primary] napps> 

rs0 [direct: primary] napps> db.flows.countDocuments()
1009

During these local tests I always had 1000+ flows installed, no other issues were observed including during kytosd restarts

End-to-End Tests

I'll dispatch an execution, but I don't expect surprises.

[viniarck]

There will be future work to further augment and/or optimize index #161, but for now I decided to only cover the minimum necessary to minimize changes and risk to impact on other queries. I've changed priority to be descending since that's how it's being sorted and queried when finding flows.