chore: use errors.New to replace fmt.Errorf with no parameters will much better

Signed-off-by: ChengenH <hce19970702@gmail.com>

README.md

@@ -302,7 +302,7 @@ You can retrieve an existing bucket using the `Tx.Bucket()` function:
 db.Update(func(tx *bolt.Tx) error {
 	b := tx.Bucket([]byte("MyBucket"))
 	if b == nil {
-		return fmt.Errorf("bucket does not exist")
+		return errors.New("bucket does not exist")
 	}
 	return nil
 })

cmd/bbolt/command_surgery.go

@@ -44,7 +44,7 @@ func (o *surgeryBaseOptions) AddFlags(fs *pflag.FlagSet) {
 
 func (o *surgeryBaseOptions) Validate() error {
 	if o.outputDBFilePath == "" {
-		return fmt.Errorf("output database path wasn't given, specify output database file path with --output option")
+		return errors.New("output database path wasn't given, specify output database file path with --output option")
 	}
 	return nil
 }

cmd/bbolt/main.go

@@ -392,7 +392,7 @@ func (cmd *pageItemCommand) Run(args ...string) error {
 	}
 
 	if options.keyOnly && options.valueOnly {
-		return fmt.Errorf("The --key-only or --value-only flag may be set, but not both.")
+		return errors.New("The --key-only or --value-only flag may be set, but not both.")
 	}
 
 	// Require database path and page id.
@@ -1675,7 +1675,7 @@ func (cmd *compactCommand) Run(args ...string) (err error) {
 	} else if err != nil {
 		return err
 	} else if cmd.DstPath == "" {
-		return fmt.Errorf("output file required")
+		return errors.New("output file required")
 	}
 
 	// Require database paths.

db.go

@@ -562,7 +562,7 @@ func (db *DB) mmapSize(size int) (int, error) {
 
 	// Verify the requested size is not above the maximum allowed.
 	if size > maxMapSize {
-		return 0, fmt.Errorf("mmap too large")
+		return 0, errors.New("mmap too large")
 	}
 
 	// If larger than 1GB then grow by 1GB at a time.