fix fixture for closedfile regtest

[braingram]

While updating fixtures in #8327 the run_image3_closedfile fixture was changed from:

def run_image3_closedfile(rtdata, jail):

to

def run_image3_closedfile(rtdata_module):

The use of rtdata_module change the directory where the fixture files are written. The files are written to a directory path ending in .../test_nircam_image_rtdata_module0
However test_image3_closedfile uses a different directory to check for the files (due to the conflicting rtdata fixture):

jwst/jwst/regtest/test_nircam_image.py

Lines 182 to 183 in 1c054d8

	@pytest.mark.bigdata
	def test_image3_closedfile(run_image3_closedfile, rtdata, fitsdiff_default_kwargs):

It checks a directory with a path ending in: .../test_image3_closedfile0

This PR uses rtdata instead to allow the paths to match.

Checklist for maintainers

• added entry in CHANGES.rst within the relevant release section
• updated or added relevant tests
• updated relevant documentation
• added relevant milestone
• added relevant label(s)
• ran regression tests, post a link to the Jenkins job below.
  How to run regression tests on a PR
• Make sure the JIRA ticket is resolved properly

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 75.66%. Comparing base (2fb073e) to head (fa71e19).
Report is 12 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #8387      +/-   ##
==========================================
+ Coverage   75.31%   75.66%   +0.34%     
==========================================
  Files         474      476       +2     
  Lines       38965    39434     +469     
==========================================
+ Hits        29345    29836     +491     
+ Misses       9620     9598      -22     

Flag	Coverage Δ		*Carryforward flag
nightly	77.63% <ø> (+0.30%)	⬆️	Carriedforward from 2fb073e

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