Fix TaskDoc.from_directory when dir_name != "." (#873)

* Fix issue with using dir_name != ./ in emmet.core.tasks.TaskDoc

* Revert previous change - actual fix is using path relative to dir_name of TaskDoc.from_directory

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Co-authored-by: esoteric-ephemera <aaronkaplan@Aarons-MBP.dhcp.lbl.gov>

emmet-core/emmet/core/tasks.py

@@ -951,16 +951,17 @@ def _get_task_files(files, suffix=""):
         vol_files = []
         elph_poscars = []
         for file in files:
+            file_no_path = file.relative_to(path)
             if file.match(f"*vasprun.xml{suffix}*"):
-                vasp_files["vasprun_file"] = file
+                vasp_files["vasprun_file"] = file_no_path
             elif file.match(f"*OUTCAR{suffix}*"):
-                vasp_files["outcar_file"] = file
+                vasp_files["outcar_file"] = file_no_path
             elif file.match(f"*CONTCAR{suffix}*"):
-                vasp_files["contcar_file"] = file
+                vasp_files["contcar_file"] = file_no_path
             elif any(file.match(f"*{f}{suffix}*") for f in volumetric_files):
-                vol_files.append(file)
+                vol_files.append(file_no_path)
             elif file.match(f"*POSCAR.T=*{suffix}*"):
-                elph_poscars.append(file)
+                elph_poscars.append(file_no_path)
 
         if len(vol_files) > 0:
             # add volumetric files if some were found or other vasp files were found