remove outdated codes (#17140)

* remove unnecessary when statement

* remove outdated codes

lib/pure/collections/sequtils.nim

@@ -326,7 +326,6 @@ func distribute*[T](s: seq[T], num: Positive, spread = true): seq[seq[T]] =
   if num < 2:
     result = @[s]
     return
-  let num = int(num) # XXX probably only needed because of .. bug
 
   # Create the result and calculate the stride size and the remainder if any.
   result = newSeq[seq[T]](num)

lib/pure/strtabs.nim

@@ -300,7 +300,6 @@ proc raiseFormatException(s: string) =
 
 proc getValue(t: StringTableRef, flags: set[FormatFlag], key: string): string =
   if hasKey(t, key): return t.getOrDefault(key)
-  # hm difficult: assume safety in taint mode here. XXX This is dangerous!
   when defined(js) or defined(nimscript) or defined(Standalone):
     result = ""
   else: