Fix remaining wsl_v5 whitespace findings (refs #61)

Insert the blank line wsl_v5 requires above `defer` and `go`
statements that share no variables with the statement above them.
Applied mechanically via `make lint-fix`; the diff is 60 added blank
lines and nothing else.

internal/database/database_test.go

@@ -19,6 +19,7 @@ func TestDatabase(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to create database: %v", err)
 	}
+
 	defer func() {
 		err := db.Close()
 		if err != nil {
@@ -73,6 +74,7 @@ func TestDatabaseConcurrentAccess(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to create database: %v", err)
 	}
+
 	defer func() {
 		err := db.Close()
 		if err != nil {
@@ -182,6 +184,7 @@ func TestApplyMigrations_Idempotent(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to open database: %v", err)
 	}
+
 	defer func() {
 		err := conn.Close()
 		if err != nil {
@@ -239,6 +242,7 @@ func TestBootstrapMigrationsTable_FreshDatabase(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed to open database: %v", err)
 	}
+
 	defer func() {
 		err := conn.Close()
 		if err != nil {