Trim configuration value string which contains blank prefix or suffix

[hangc0276]

Motivation

For broker.conf and proxy.conf, if user configure value string which contains blank prefix or suffix, it will parse failed for related configuration and cause broker startup failed.

For example, if user configure the metadataStoreUrl=" zk:my-zk-1:2181,my-zk-2:2181,my-zk-3:2181 ", we will connect to zookeeper server failed due to the blank suffix, and it's hard to debug.

Modifications

1. Trim the value string on PulsarConfigurationLoader load process.

Verifying this change

• Make sure that the change passes the CI checks.

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This change is a trivial rework / code cleanup without any test coverage.

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This change is already covered by existing tests, such as (please describe tests).

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This change added tests and can be verified as follows:

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• Added integration tests for end-to-end deployment with large payloads (10MB)
• Extended integration test for recovery after broker failure

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

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• 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)
• The rest endpoints: (yes / no)
• The admin cli options: (yes / no)
• Anything that affects deployment: (yes / no / don't know)

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