small adjustments regarding runtime

star.wdl

@@ -13,7 +13,7 @@ task Star {
     String? twopassMode
     Array[String]? outSAMattrRGline
 
-    Float? memory
+    Int? memory
 
     #TODO needs to be extended for all possible output extensions
     Map[String, String] samOutputNames = {"BAM SortedByCoordinate": "sortedByCoord.out.bam"}

stringtie.wdl

@@ -28,6 +28,6 @@ task Stringtie {
     }
 
     runtime {
-        threads: select_first([threads])
+        threads: select_first([threads, 1])
     }
 }
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