adjusted agg_multiselect_history incremental logi

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What change(s) does this PR introduce?

This PR adjusts the incremental logic within int_jira__agg_multiselect_history to properly capture the relevant records since the last incremental run.

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.)

As this PR implements an update to an incremental model, we will want to highlight this as a breaking change and for users to run --full-refresh on the first run after installing the latest version of the package.

Is this PR in response to a previously created Issue

[X] Yes, Issue #41
[ ] 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 - [X] 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_jira

adjusted agg_multiselect_history incremental logi #48