WIP : Adding error logs for import command

[rahuld-dev]

Q	A
Bug fix? (use the a.b branch)	[ ]
New feature/enhancement? (use the a.x branch)	[ ]
Deprecations?	[ ]
BC breaks? (use the c.x branch)	[ ]
Automated tests included?	[ ]
Related user documentation PR URL	mautic/mautic-documentation#...
Related developer documentation PR URL	mautic/developer-documentation#...
Issue(s) addressed	Fixes #...

Description:

Steps to test this PR:

1. Open this PR on Gitpod or pull down for testing locally (see docs on testing PRs here)

[codecov]

Codecov Report

Attention: Patch coverage is 81.81818% with 2 lines in your changes are missing coverage. Please review.

Project coverage is 61.01%. Comparing base (032a462) to head (9c24d7a).

Additional details and impacted files

@@             Coverage Diff              @@
##                5.x   #13543      +/-   ##
============================================
+ Coverage     61.00%   61.01%   +0.01%     
- Complexity    33931    33932       +1     
============================================
  Files          2236     2236              
  Lines        101444   101453       +9     
============================================
+ Hits          61885    61904      +19     
+ Misses        39559    39549      -10     

Files	Coverage Δ
app/bundles/LeadBundle/Command/ImportCommand.php	86.00% <81.81%> (+10.39%)	⬆️

... and 3 files with indirect coverage changes