fix(mp7particledata): update dtype comparison for unstructured partlo…

…cs (#1071)

change dtypein comparison against dtype variable. dtypein was being compared against itself thus partlocs dtype didn't update

Co-authored-by: rodrperezi <rodrperezi@gmail.com>

flopy/modpath/mp7particledata.py

@@ -173,7 +173,7 @@ def __init__(
             partlocs = np.array(partlocs, dtype=dtype)
         elif isinstance(partlocs, np.ndarray):
             dtypein = partlocs.dtype
-            if dtypein != partlocs.dtype:
+            if dtypein != dtype:
                 partlocs = np.array(partlocs, dtype=dtype)
         else:
             msg = (