Add SnapshotStore SaveSnapshot spec from TCK (#271)

src/Akka.Persistence.PostgreSql.Tests/PostgreSqlSnapshotStoreSaveSnapshotSpec.cs

@@ -0,0 +1,41 @@
+using Akka.Configuration;
+using Akka.Persistence.TCK.Snapshot;
+using Xunit;
+using Xunit.Abstractions;
+
+namespace Akka.Persistence.PostgreSql.Tests;
+
+[Collection("PostgreSqlSpec")]
+public class PostgreSqlSnapshotStoreSaveSnapshotSpec: SnapshotStoreSaveSnapshotSpec
+{
+    private static Config Initialize(PostgresFixture fixture)
+    {
+        //need to make sure db is created before the tests start
+        DbUtils.Initialize(fixture);
+
+        var config = @$"
+                akka.persistence {{
+                    publish-plugin-commands = on
+                    snapshot-store {{
+                        plugin = ""akka.persistence.snapshot-store.postgresql""
+                        postgresql {{
+                            class = ""Akka.Persistence.PostgreSql.Snapshot.PostgreSqlSnapshotStore, Akka.Persistence.PostgreSql""
+                            plugin-dispatcher = ""akka.actor.default-dispatcher""
+                            table-name = snapshot_store
+                            schema-name = public
+                            auto-initialize = on
+                            connection-string = ""{DbUtils.ConnectionString}""
+                            stored-as = bytea
+                        }}
+                    }}
+                }}
+                akka.test.single-expect-default = 10s";
+
+        return ConfigurationFactory.ParseString(config);
+    }
+
+    public PostgreSqlSnapshotStoreSaveSnapshotSpec(ITestOutputHelper output, PostgresFixture fixture)
+        : base(Initialize(fixture), nameof(PostgreSqlSnapshotStoreSaveSnapshotSpec), output: output)
+    {
+    }
+}