Add SQL replay checkpoint object to SQL (#868)

* Add SQL replay checkpoint object to Datastore

This will be part of the asynchronous commit-log replay to SQL. Whenever
we successfully export commits up to a particular time, we should
persist that time so we don't replay the same commits again (it is not
idempotent)

* Move SqlReplayCheckpoint from DS to SQL

* Responses to CR

db/src/main/resources/sql/schema/db-schema.sql.generated

@@ -655,6 +655,12 @@
         primary key (id)
     );
 
+    create table "SqlReplayCheckpoint" (
+       revision_id int8 not null,
+        last_replay_time timestamptz,
+        primary key (revision_id)
+    );
+
     create table "Tld" (
        tld_name text not null,
         add_grace_period_length interval not null,

db/src/main/resources/sql/schema/nomulus.golden.sql

@@ -948,6 +948,16 @@ CREATE SEQUENCE public."SignedMarkRevocationList_revision_id_seq"
 ALTER SEQUENCE public."SignedMarkRevocationList_revision_id_seq" OWNED BY public."SignedMarkRevocationList".revision_id;
 
 
+--
+-- Name: SqlReplayCheckpoint; Type: TABLE; Schema: public; Owner: -
+--
+
+CREATE TABLE public."SqlReplayCheckpoint" (
+    revision_id bigint NOT NULL,
+    last_replay_time timestamp with time zone NOT NULL
+);
+
+
 --
 -- Name: Tld; Type: TABLE; Schema: public; Owner: -
 --
@@ -1346,6 +1356,14 @@ ALTER TABLE ONLY public."SignedMarkRevocationList"
     ADD CONSTRAINT "SignedMarkRevocationList_pkey" PRIMARY KEY (revision_id);
 
 
+--
+-- Name: SqlReplayCheckpoint SqlReplayCheckpoint_pkey; Type: CONSTRAINT; Schema: public; Owner: -
+--
+
+ALTER TABLE ONLY public."SqlReplayCheckpoint"
+    ADD CONSTRAINT "SqlReplayCheckpoint_pkey" PRIMARY KEY (revision_id);
+
+
 --
 -- Name: Tld Tld_pkey; Type: CONSTRAINT; Schema: public; Owner: -
 --