Describe the bug
aiokafka.structs.BrokerMetadata#nodeId is typed as an int, however it is sometimes assigned str values:

• It is assigned a str here
• Also assigned a str here
• It is assigned an int here (the value is passed in to add_coordinator(...) here, the value of resp.coordinator_id is an integer, as defined here, and here)

Expected behaviour
aiokafka.structs.BrokerMetadata#nodeId is correctly typed as a typing.Union[int, str]

Value reads do not seem to care too much about the type of this field, as long as:

• It is unique
• It can be used as a dict key

So no further changes should be needed

Alternative is to make it a str field, and convert int to str where int values are currently being assigned.

Environment (please complete the following information):
N/A this is a typing bug, I generally use Pyright to type check.

Additional observations
Also note that the name nodeId is camel-case, whereas Python prefers (and the rest of the code-base are) snake-case. I will provide a PR to resolve the above issue shortly. I am happy to rename nodeId to node_id as well, if that is desired, but I do not plan to, to minimize the changes introduced by the PR.