feat: add support for update command

[majinghe]

Backupground

Currently, rc doesn't support rc admin update command and use can not upgrade the RustFS instance.

Expected

rc should have the same behavior with mc, and user can use rc admin update upgrade the cluster with roll-out method.

Reference

mc admin update command usage

mc admin update --help
───────────────────────────────────────────────────────────────── (q)uit/esc
stdout [$MC_DISABLE_PAGER]                                                  
  --no-color                       disable color theme [$MC_NO_COLOR]       
  --json                           enable JSON lines formatted output       
[$MC_JSON]                                                                  
  --debug                          enable debug output [$MC_DEBUG]          
  --resolve value                  resolves HOST[:PORT] to an IP address.   
Example: minio.local:9000=10.10.75.1 [$MC_RESOLVE]                          
  --insecure                       disable SSL certificate verification     
[$MC_INSECURE]                                                              
  --limit-upload value             limits uploads to a maximum rate in      
KiB/s,                                                                      
MiB/s, GiB/s. (default: unlimited) [$MC_LIMIT_UPLOAD]                       
  --limit-download value           limits downloads to a maximum rate in    
KiB/s, MiB/s, GiB/s. (default: unlimited) [$MC_LIMIT_DOWNLOAD]              
  --custom-header value, -H value  add custom HTTP header to the request.   
'key:value' format.                                                         
  --help, -h                       show help                                
                                                                            
EXAMPLES:                                                                   
  1. Update MinIO server represented by its alias 'play'.                   
     $ mc admin update play/                                                
                                                                            
  2. Update all MinIO servers in a distributed setup, represented by its    
alias 'mydist'.                                                             
     $ mc admin update mydist/                                              
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