Fix passing config to CameraCalibrator

[watsonjj]

Passing a config to CameraCalibrator currently raises the error:

ValueError: Only one of `config` or `parent` allowed If you create a Component as part of another, give `parent=self` and not `config`

This PR fixes that.

[codecov]

Codecov Report

Merging #1042 into master will increase coverage by 0.01%.
The diff coverage is 100%.

@@            Coverage Diff             @@
##           master    #1042      +/-   ##
==========================================
+ Coverage   83.45%   83.47%   +0.01%     
==========================================
  Files         186      186              
  Lines       10531    10539       +8     
==========================================
+ Hits         8789     8797       +8     
  Misses       1742     1742

Impacted Files	Coverage Δ
ctapipe/calib/camera/calibrator.py	100% <ø> (ø)	⬆️
ctapipe/calib/camera/tests/test_calibrator.py	100% <100%> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 6a243b2...1c7d703. Read the comment docs.