sa: Truncate notBefore times on issuedNames (#7568)

We only care about the date of an issuedName, not the exact time, and
this may reduce the size of the index somewhat.

---------

Co-authored-by: Samantha Frank <hello@entropy.cat>

sa/model.go

@@ -1008,7 +1008,7 @@ func addIssuedNames(ctx context.Context, queryer db.Queryer, cert *x509.Certific
 		err = multiInserter.Add([]interface{}{
 			ReverseName(name),
 			core.SerialToString(cert.SerialNumber),
-			cert.NotBefore,
+			cert.NotBefore.Truncate(24 * time.Hour),
 			isRenewal,
 		})
 		if err != nil {

sa/sa_test.go

@@ -1077,6 +1077,7 @@ func TestAddIssuedNames(t *testing.T) {
 	serial := big.NewInt(1)
 	expectedSerial := "000000000000000000000000000000000001"
 	notBefore := time.Date(2018, 2, 14, 12, 0, 0, 0, time.UTC)
+	expectedNotBefore := notBefore.Truncate(24 * time.Hour)
 	placeholdersPerName := "(?,?,?,?)"
 	baseQuery := "INSERT INTO issuedNames (reversedName,serial,notBefore,renewal) VALUES"
 
@@ -1097,7 +1098,7 @@ func TestAddIssuedNames(t *testing.T) {
 			ExpectedArgs: []interface{}{
 				"uk.co.example",
 				expectedSerial,
-				notBefore,
+				expectedNotBefore,
 				false,
 			},
 		},
@@ -1110,11 +1111,11 @@ func TestAddIssuedNames(t *testing.T) {
 			ExpectedArgs: []interface{}{
 				"uk.co.example",
 				expectedSerial,
-				notBefore,
+				expectedNotBefore,
 				false,
 				"xyz.example",
 				expectedSerial,
-				notBefore,
+				expectedNotBefore,
 				false,
 			},
 		},
@@ -1127,7 +1128,7 @@ func TestAddIssuedNames(t *testing.T) {
 			ExpectedArgs: []interface{}{
 				"uk.co.example",
 				expectedSerial,
-				notBefore,
+				expectedNotBefore,
 				true,
 			},
 		},
@@ -1140,11 +1141,11 @@ func TestAddIssuedNames(t *testing.T) {
 			ExpectedArgs: []interface{}{
 				"uk.co.example",
 				expectedSerial,
-				notBefore,
+				expectedNotBefore,
 				true,
 				"xyz.example",
 				expectedSerial,
-				notBefore,
+				expectedNotBefore,
 				true,
 			},
 		},