Failing to create BQ table when multiple Option items are added

[darrenhaken]

Describe the bug

When creating a BQ table and you have multiple items within the Options BQ will fail as it expects a comma-separated list. The current behaviour adds no comma.

Steps To Reproduce

Use DBT Utils to create a temp table, this adds multiple options to a BQ table.

Expected behaviour

A clear and concise description of what you expected to happen.

Screenshots and log output

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System information

Which database are you using dbt with?

• postgres
• redshift
• bigquery
• snowflake
• other (specify: ____________)

**The output of dbt --version: **

0.14.2

The operating system you're using:
Mac
The output of python --version:
2.7.10

Additional context

Add any other context about the problem here.