Database changes to support tf state version replicaiton

What does this MR do?

Database changes to support replicating terraform versioned states. First issue in &4216 (closed)

Fixes #237924 (closed)

Database Info

The terraform_state_versions table was introduced in !35211 (merged) just today (9/16), so it shouldn't have much in it yet.

Up Migration (Primary Database)

= 20200915152641 AddVerificationStateToTerraformStateVersion: migrating ======
-- change_table(:terraform_state_versions)
   -> 0.0055s
== 20200915152641 AddVerificationStateToTerraformStateVersion: migrated (0.0055s) 

== 20200915164448 AddVerificationFailureLimitToTerraformStateVersion: migrating 
-- transaction_open?()
   -> 0.0000s
-- execute("ALTER TABLE terraform_state_versions\nADD CONSTRAINT tf_state_versions_verification_failure_text_limit\nCHECK ( char_length(verification_failure) <= 255 )\nNOT VALID;\n")
   -> 0.0010s
-- execute("ALTER TABLE terraform_state_versions VALIDATE CONSTRAINT tf_state_versions_verification_failure_text_limit;")
   -> 0.0007s
== 20200915164448 AddVerificationFailureLimitToTerraformStateVersion: migrated (0.0103s) 

== 20200915164844 AddVerificationFailureIndexToTerraformStateVersion: migrating 
-- transaction_open?()
   -> 0.0000s
-- index_exists?(:terraform_state_versions, :verification_failure, {:where=>"(verification_failure IS NOT NULL)", :name=>"terraform_state_versions_verification_failure_partial", :algorithm=>:concurrently})
   -> 0.0021s
-- add_index(:terraform_state_versions, :verification_failure, {:where=>"(verification_failure IS NOT NULL)", :name=>"terraform_state_versions_verification_failure_partial", :algorithm=>:concurrently})
   -> 0.0024s
-- transaction_open?()
   -> 0.0000s
-- index_exists?(:terraform_state_versions, :verification_checksum, {:where=>"(verification_checksum IS NOT NULL)", :name=>"terraform_state_versions_verification_checksum_partial", :algorithm=>:concurrently})
   -> 0.0013s
-- add_index(:terraform_state_versions, :verification_checksum, {:where=>"(verification_checksum IS NOT NULL)", :name=>"terraform_state_versions_verification_checksum_partial", :algorithm=>:concurrently})
   -> 0.0022s
== 20200915164844 AddVerificationFailureIndexToTerraformStateVersion: migrated (0.0091s) 

Down Migrations (Primary Database)

== 20200915164844 AddVerificationFailureIndexToTerraformStateVersion: reverting 
-- transaction_open?()
   -> 0.0000s
-- indexes(:terraform_state_versions)
   -> 0.0033s
-- remove_index(:terraform_state_versions, {:algorithm=>:concurrently, :name=>"terraform_state_versions_verification_failure_partial"})
   -> 0.0029s
-- transaction_open?()
   -> 0.0000s
-- indexes(:terraform_state_versions)
   -> 0.0018s
-- remove_index(:terraform_state_versions, {:algorithm=>:concurrently, :name=>"terraform_state_versions_verification_checksum_partial"})
   -> 0.0012s
== 20200915164844 AddVerificationFailureIndexToTerraformStateVersion: reverted (0.0104s) 

== 20200915164448 AddVerificationFailureLimitToTerraformStateVersion: reverting 
-- execute("ALTER TABLE terraform_state_versions\nDROP CONSTRAINT IF EXISTS tf_state_versions_verification_failure_text_limit\n")
   -> 0.0008s
== 20200915164448 AddVerificationFailureLimitToTerraformStateVersion: reverted (0.0038s) 

== 20200915152641 AddVerificationStateToTerraformStateVersion: reverting ======
-- remove_column(:terraform_state_versions, :verification_failure, :text, {})
   -> 0.0016s
-- remove_column(:terraform_state_versions, :verification_checksum, :binary, {:using=>"verification_checksum::bytea"})
   -> 0.0002s
-- remove_column(:terraform_state_versions, :verified_at, :datetime_with_timezone, {})
   -> 0.0002s
-- remove_column(:terraform_state_versions, :verification_retry_at, :datetime_with_timezone, {})
   -> 0.0002s
-- remove_column(:terraform_state_versions, :verification_retry_count, :integer, {:limit=>2})
   -> 0.0002s
== 20200915152641 AddVerificationStateToTerraformStateVersion: reverted (0.0071s) 

Up Migration (Geo Tracking Database)

== 20200915152620 CreateTerraformStateVersionRegistry: migrating ==============
-- table_exists?(:terraform_state_version_registry)
   -> 0.0003s
-- create_table(:terraform_state_version_registry, {:id=>:bigserial, :force=>:cascade})
   -> 0.0100s
-- transaction_open?()
   -> 0.0000s
-- execute("ALTER TABLE terraform_state_version_registry\nADD CONSTRAINT check_7827f2d2cf\nCHECK ( char_length(last_sync_failure) <= 255 )\nNOT VALID;\n")
   -> 0.0006s
-- execute("ALTER TABLE terraform_state_version_registry VALIDATE CONSTRAINT check_7827f2d2cf;")
   -> 0.0006s
== 20200915152620 CreateTerraformStateVersionRegistry: migrated (0.0167s) =====

Down Migration (Geo Tracking Database)

== 20200915152620 CreateTerraformStateVersionRegistry: reverting ==============
-- drop_table(:terraform_state_version_registry)
   -> 0.0035s
== 20200915152620 CreateTerraformStateVersionRegistry: reverted (0.0036s) =====

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