Modify atlas test for short commit hashes (#18619)

* test commit hashes support

* Update testdata.nim

* remove extra newlines

tools/atlas/packagesjson.nim

@@ -70,7 +70,6 @@ proc search*(pkgList: seq[Package]; terms: seq[string]) =
   var found = false
   template onFound =
     echo pkg
-    echo("")
     found = true
     break forPackage
 
@@ -88,7 +87,6 @@ proc search*(pkgList: seq[Package]; terms: seq[string]) =
               onFound()
     else:
       echo(pkg)
-      echo(" ")
 
   if not found and terms.len > 0:
     echo("No package found.")