fix: optimize .map.filter with .flatMap

Co-authored-by: Jordan Harband <[email protected]>

Author: reggi

lib/commands/publish.js

@@ -214,8 +214,10 @@ class Publish extends BaseCommand {
         return null
       }
       const ordered = Object.keys(packument?.versions)
-        .map(v => new semver.SemVer(v))
-        .filter(v => !v.prerelease.length)
+        .flatMap(v => {
+          const s = new semver.SemVer(v)
+          return s.prerelease.length > 0 ? [] : s;
+        })
         .sort((a, b) => b.compare(a))
       return ordered.length >= 1 ? ordered[0].version : null
     } catch (e) {