BigQuery ST_GEOGFROMGEOJSON breaks parser when using make_valid parameter

[daaain]

https://cloud.google.com/bigquery/docs/reference/standard-sql/geography_functions#st_geogfromgeojson

Expected Behaviour

Pass

Observed Behaviour

L:  25 | P:  89 | L027 | Unqualified reference 'make_valid' found in select with
                       | more than one referenced table/view.
L:  25 | P:  99 |  PRS | Found unparsable section: ' => true'

Steps to Reproduce

Using the optional make_valid parameter in ST_GEOGFROMGEOJSON breaks the parser.

For example:

st_geogfromgeojson(lsoa.geography, make_valid => true)

Version

app@27fc52961e2b:/app$ sqlfluff --version
sqlfluff, version 0.5.6
app@27fc52961e2b:/app$ python --version
Python 3.7.10

Configuration

[sqlfluff]
templater = dbt
dialect = bigquery
exclude_rules = L031

[sqlfluff:rules]
tab_space_size = 2
max_line_length = 100

[sqlfluff:rules:L030]
capitalisation_policy = lower

[barrywhart]

Here's a full SELECT query that produces the issue:

SELECT ST_GEOGFROMGEOJSON('{"type":"LineString","coordinates":[[1,2],[4,5]]}', make_valid => true)