Field "database" of type typing.Union[str, NoneType] is missing in dbt.adapters.mysql.connections.MySQLCredentials instance

[ghost]

Describe the bug

A clear and concise description of what the bug is. What command did you run? What happened?
Run - dbt debug
Encountered an error:
Field "database" of type typing.Union[str, NoneType] is missing in dbt.adapters.mysql.connections.MySQLCredentials instance

Steps To Reproduce

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Expected behavior

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Screenshots and log output

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The output of dbt --version:

installed version: 0.19.2
   latest version: 0.19.2

Up to date!

Plugins:
  - bigquery: 0.19.2
  - mysql: 0.19.0
  - mysql5: 0.19.0
  - postgres: 0.19.2
  - redshift: 0.19.2
  - snowflake: 0.19.2

The operating system you're using:
windows 10

The output of python --version:
python 3.6

Additional context

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