Example file path update

[hpohekar]

Implemented suggestions given by @mkundu1 and @raph-luc

>>> from ansys.fluent.core import examples                      
>>> filepath = examples.path("elbow_param.cas.h5")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "D:\Repos\pyfluent\src\ansys\fluent\core\examples\downloads.py", line 144, in path
    raise FileNotFoundError(f"{filename} does not exist.")
FileNotFoundError: elbow_param.cas.h5 does not exist.
>>> path = examples.download_file("elbow_param.cas.h5", "pyfluent/mixing_elbow")
Checking if specified file already exists...
File does not exist. Downloading specified file...
Download successful. File path:
C:\Users\hpohekar\AppData\Local\Ansys\ansys_fluent_core\examples\elbow_param.cas.h5
>>> path
'C:\\Users\\hpohekar\\AppData\\Local\\Ansys\\ansys_fluent_core\\examples\\elbow_param.cas.h5'
>>> filepath = examples.path("elbow_param.cas.h5")                               
>>> filepath
'C:\\Users\\hpohekar\\AppData\\Local\\Ansys\\ansys_fluent_core\\examples\\elbow_param.cas.h5'
>>> filepath = examples.path(path)                 
>>> filepath                       
'C:\\Users\\hpohekar\\AppData\\Local\\Ansys\\ansys_fluent_core\\examples\\elbow_param.cas.h5'
>>>