Include rebar3_hex in project_plugins, not plugins

[newmanjeff]

Proposed Changes

Moves the rebar3_hex plugin from "plugins" to "project_plugins." Including the plugin within the "plugin" section means all projects the include credentials-obfuscation as a dependency must also include the rebar3_hex plugin. Note the documentation:

NOTE : Be sure not to add rebar3_hex to the plugins section within a projects rebar3 config as this will become a dependency for others downloading your package from hex.pm

Types of Changes

What types of changes does your code introduce to this project?
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• Bug fix (non-breaking change which fixes issue Remove rebar3_hex plugin from rebar.config #22
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation (correction or otherwise)
• Cosmetics (whitespace, appearance)

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• I have read the CONTRIBUTING.md document
• I have signed the CA (see https://cla.pivotal.io/sign/rabbitmq)
• All tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• Any dependent changes have been merged and published in related repositories

Further Comments

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[michaelklishin]

Thank you. I'll cut a new release some time tomorrow.

[isaacsanders]

@michaelklishin A new release was never made

[lukebakken]

@isaacsanders I'm getting the release now.

[lukebakken]

@isaacsanders @newmanjeff - https://github.com/rabbitmq/credentials-obfuscation/releases/tag/v3.3.0

[isaacsanders]

@isaacsanders I'm getting the release now.

Thank you!