[fix] Fix data race in checkAndCleanIdleConnections

[RobertIndie]

Fixes #978

Motivation

From the data race log of the issue:

2023-03-07T02:05:50.0096902Z WARNING: DATA RACE
2023-03-07T02:05:50.0097176Z Read at 0x00c0003bb298 by goroutine 111:
2023-03-07T02:05:50.0097767Z   github.com/apache/pulsar-client-go/pulsar/internal.(*connectionPool).checkAndCleanIdleConnections()
2023-03-07T02:05:50.0098468Z       /pulsar/pulsar-client-go/pulsar/internal/connection_pool.go:157 +0x24d
2023-03-07T02:05:50.0099058Z   github.com/apache/pulsar-client-go/pulsar/internal.StartCleanConnectionsTask.func1()
2023-03-07T02:05:50.0099727Z       /pulsar/pulsar-client-go/pulsar/internal/helper.go:25 +0x47
2023-03-07T02:05:50.0099934Z 
2023-03-07T02:05:50.0100066Z Previous write at 0x00c0003bb298 by goroutine 69:
2023-03-07T02:05:50.0100537Z   github.com/apache/pulsar-client-go/pulsar/internal.(*connection).connect()
2023-03-07T02:05:50.0101126Z       /pulsar/pulsar-client-go/pulsar/internal/connection.go:277 +0x5d2
2023-03-07T02:05:50.0101649Z   github.com/apache/pulsar-client-go/pulsar/internal.(*connection).start.func1()
2023-03-07T02:05:50.0102222Z       /pulsar/pulsar-client-go/pulsar/internal/connection.go:230 +0x34

We can see that the read access of c.log here:

pulsar-client-go/pulsar/internal/connection_pool.go

Line 157 in c595677

c.log.Debugf("Closed connection due to inactivity.")

is conflict with the write access of c.log here:

pulsar-client-go/pulsar/internal/connection.go

Line 277 in c595677

c.log = c.log.SubLogger(log.Fields{"local_addr": c.cnx.LocalAddr()})

This caused the data race.

Modifications

• Using p.log to avoid accessing the c.log

Verifying this change

This change is already covered by existing tests

Does this pull request potentially affect one of the following parts:

If yes was chosen, please highlight the changes

• Dependencies (does it add or upgrade a dependency): (yes / no)
• The public API: (yes / no)
• The schema: (yes / no / don't know)
• The default values of configurations: (yes / no)
• The wire protocol: (yes / no)

Documentation

• Does this pull request introduce a new feature? (yes / no)
• If yes, how is the feature documented? (not applicable / docs / GoDocs / not documented)
• If a feature is not applicable for documentation, explain why?
• If a feature is not documented yet in this PR, please create a followup issue for adding the documentation