sql-server: Add behavior: auto_gc_behavior: enable.

[reltuk]

When Auto GC is enabled, the running sql-server will periodically collect a Dolt database that is growing in size. This behavior is currently experimental. Tuning the behavior around how often to collect is ongoing work.

[coffeegoddd]

@reltuk DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
dc4b94d	ok	5937457

version	total_tests
dc4b94d	5937457

correctness_percentage
100.0

[coffeegoddd]

@reltuk DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
9b53d20	ok	5937457

version	total_tests
9b53d20	5937457

correctness_percentage
100.0

[coffeegoddd]

@reltuk DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
62e5032	ok	5937457

version	total_tests
62e5032	5937457

correctness_percentage
100.0

[coffeegoddd]

@reltuk DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
f509d98	ok	5937457

version	total_tests
f509d98	5937457

correctness_percentage
100.0

[coffeegoddd]

@coffeegoddd DOLT

comparing_percentages
100.000000 to 100.000000

version	result	total
10dfcec	ok	5937457

version	total_tests
10dfcec	5937457

correctness_percentage
100.0