TUN-5262: Improvements to max-fetch-size that allow to deal with large number of tunnels in account

* `max-fetch-size` can now be set up in the config YAML
 * we no longer pass that to filter commands that filter by name
 * flag changed to signed int since altsrc does not support UInt flags
 * we now look up each non UUID (to convert it to a UUID) when needed, separately

cmd/cloudflared/tunnel/cmd.go

@@ -646,12 +646,12 @@ func tunnelFlags(shouldHide bool) []cli.Flag {
 			Value:  "https://api.trycloudflare.com",
 			Hidden: true,
 		}),
-		&cli.UintFlag{
+		altsrc.NewIntFlag(&cli.IntFlag{
 			Name:    "max-fetch-size",
 			Usage:   `The maximum number of results that cloudflared can fetch from Cloudflare API for any listing operations needed`,
 			EnvVars: []string{"TUNNEL_MAX_FETCH_SIZE"},
 			Hidden:  true,
-		},
+		}),
 		selectProtocolFlag,
 		overwriteDNSFlag,
 	}...)