Feature/Label-Source-Addition

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Fivetran created PR

What change(s) does this PR introduce?

This PR adds the label source table. This was necessary as the issue_label depreciated the label column. The respective label information will now be synced within the label table.

Additionally, a few minor updates were made to the issue_label table and some spelling updates were applied.

Does this PR introduce a breaking change?

[X] Yes (please provide breaking change details below.)
[ ] No (please provide explanation how the change is non breaking below.)

Since this PR removes a field from the issue_label table and adds a new source table, this will be reflected as a breaking change.

Is this PR in response to a previously created Issue

[X] Yes, Issue #21
[ ] No

How did you test the PR changes?

- [X] CircleCi - [ ] Other (please provide additional testing details below) **Select which warehouse(s) were used to test the PR** - [X] BigQuery - [X] Redshift - [X] Snowflake - [ ] Postgres - [ ] Databricks - [ ] Other (provide details below) **Provide an emoji that best describes your current mood** 🏷️ **Feedback** We are so excited you decided to contribute to the Fivetran community dbt package! We continue to work to improve the packages and would greatly appreciate your [feedback](https://www.surveymonkey.com/r/DQ7K7WW) on our existing dbt packages or what you'd like to see next.

fivetran / dbt_github_source

Feature/Label-Source-Addition #22