build: use golangci-lint CLI to lint files (#80)

This PR updates the linting process to use the `golangci-lint` CLI. This should guarantee major forward compatibility as the golangci-lint version is now tracked within the codebase along with other dependencies

Depends-On: #79

- [x] Targeted PR against correct branch.
- [ ] Linked to Github issue with discussion and accepted design OR link to spec that describes this work.
- [ ] Wrote unit tests.
- [x] Re-reviewed `Files changed` in the Github PR explorer.

database/postgresql/postgresql.go

@@ -101,14 +101,15 @@ func (db *Database) GetLastBlockHeight() (int64, error) {
 	stmt := `SELECT height FROM block ORDER BY height DESC LIMIT 1;`
 
 	var height int64
-	if err := db.SQL.QueryRow(stmt).Scan(&height); err != nil {
+	err := db.SQL.QueryRow(stmt).Scan(&height)
+	if err != nil {
+		if strings.Contains(err.Error(), "no rows in result set") {
+			// If no rows stored in block table, return 0 as height
+			return 0, nil
+		}
 		return 0, fmt.Errorf("error while getting last block height, error: %s", err)
 	}
 
-	if height == 0 {
-		return 0, fmt.Errorf("cannot get block height, no blocks saved")
-	}
-
 	return height, nil
 }