allow --latest without --update + reword help

it does nothing (it's the default) but doesn't need to be an error

cli/args/flags.rs

@@ -2664,10 +2664,10 @@ Display outdated dependencies:
   <p(245)>deno outdated</>
   <p(245)>deno outdated --compatible</>
 
-Update dependencies:
+Update dependencies to latest semver compatible versions:
   <p(245)>deno outdated --update</>
+Update dependencies to latest versions, ignoring semver requirements:
   <p(245)>deno outdated --update --latest</>
-  <p(245)>deno outdated --update</>
 
 Filters can be used to select which packages to act on. Filters can include wildcards (*) to match multiple packages.
   <p(245)>deno outdated --update --latest \"@std/*\"</>
@@ -2703,7 +2703,6 @@ Specific version requirements to update to can be specified:
           .help(
             "Update to the latest version, regardless of semver constraints",
           )
-          .requires("update")
           .conflicts_with("compatible"),
       )
       .arg(