docs(ssh): Update docs to reflect ssh default port is not required

internal/cmd/commands/targetscmd/ssh_funcs.go

@@ -91,7 +91,7 @@ func extraSshFlagsFuncImpl(c *SshCommand, set *base.FlagSets, f *base.FlagSet) {
 			fs.StringVar(&base.StringVar{
 				Name:   "default-port",
 				Target: &c.flagDefaultPort,
-				Usage:  "The default port to set on the target.",
+				Usage:  "Optionally, the default port to set on the target. If not specified, it will be set to 22.",
 			})
 		case "default-client-port":
 			fs.StringVar(&base.StringVar{

website/content/docs/concepts/domain-model/targets.mdx

@@ -91,8 +91,9 @@ SSH targets have the following additional attributes:
   A valid network address for the target to connect to.
   This value cannot be used alongside host sources.
 
-- `default_port` - (required)
+- `default_port` - (optional)
   The default port to set on this target.
+  If this is not specified the default port will be 22.
 
 - `egress_worker_filter` - (optional)
   A boolean expression to [filter][] which egress workers can handle sessions