Houdini Explicitly collect correct frame name even in case of single frame render when frameStart is provided

[BigRoy]

(cherry picked from commit 0f82a75)

Brief description

There was a bug in Houdini that whenever you do have a frame range set of just a single frame, e.g. 1001-1001 then collect_frames would actually eval the filename on the current frame instead of that start frame. Thus if you're writing to a file with $F the file would be named different than what the ROP node would actually output

Additional info

Here's an example error that could happen. The integrator here fails to copy the file becuase the ROP node actually rendered another file than was "collected" as expected resulting filename from the ROP node.

Instance: 
vdbcachesmoke_room (160) [1001.0 - 1001.0]
Message: 
[WinError -2147024894] The system cannot find the file specified
Line: 
933
Traceback: 
Traceback (most recent call last):
  File "C:\Program Files (x86)\OpenPype\dependencies\pyblish\plugin.py", line 522, in __explicit_process
    runner(*args)
  File "C:\Users\User\AppData\Local\pypeclub\openpype\openpype-v3.8.1\openpype\plugins\publish\integrate_new.py", line 138, in process
  File "C:\Program Files (x86)\OpenPype\dependencies\six.py", line 719, in reraise
    raise value
  File "C:\Users\User\AppData\Local\pypeclub\openpype\openpype-v3.8.1\openpype\plugins\publish\integrate_new.py", line 129, in process
  File "C:\Users\User\AppData\Local\pypeclub\openpype\openpype-v3.8.1\openpype\plugins\publish\integrate_new.py", line 597, in register
  File "C:\Users\User\AppData\Local\pypeclub\openpype\openpype-v3.8.1\openpype\plugins\publish\integrate_new.py", line 653, in integrate
  File "C:\Users\User\AppData\Local\pypeclub\openpype\openpype-v3.8.1\openpype\plugins\publish\integrate_new.py", line 699, in copy_file
  File "C:\Program Files (x86)\OpenPype\dependencies\speedcopy\__init__.py", line 289, in copyfile
    '\\\\?\\' + dest_file, None)
  File "_ctypes/callproc.c", line 933, in GetResult
OSError: [WinError -2147024894] The system cannot find the file specified

Testing notes:

1. Create a vdbCache instance to extract from frame 1001 to 1001.
2. Set current frame to 1002 in timeline.
3. Publish.

The render rop will render 1001 however the collect_frames and thus integrator thinks 1002 should be published.

Additional Context

I've also added a warning if it's rendering without a frame range set and thus renders current frame - since that is less reliable in a production environment and thus discouraged?

[BigRoy]

Sorry for that commit mess there - my app tried to be clever and exclude an edit from the commits each time. 🔥

[antirotor]

works perfectly