add missing doc strings

Author: Napalys

shared/dataflow/codeql/dataflow/VariableCapture.qll

@@ -214,6 +214,7 @@ module Flow<
   final private class CfgBb = Cfg::BasicBlock;
 
   private class BasicBlock extends CfgBb {
+    /** Gets the callable that contains this basic block. */
     Callable getEnclosingCallable() { result = basicBlockGetEnclosingCallable(this) }
   }
 

shared/util/codeql/util/Option.qll

@@ -128,6 +128,7 @@ module LocatableOption<LocationSig Location, WithLocation<Location>::LocatableTy
    * given type.
    */
   class Option extends BaseOption {
+    /** Gets the location of this option. For `None`, returns an empty location. */
     Location getLocation() {
       result = this.asSome().getLocation()
       or