Better handle nested IF statements

[kddejong]

Issue #, if available:
Fix #1211
Description of changes:

• Supported nested IF statements in IF conditions

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[codecov]

Codecov Report

Merging #1212 into master will increase coverage by 0.03%.
The diff coverage is 64.1%.

@@            Coverage Diff             @@
##           master    #1212      +/-   ##
==========================================
+ Coverage   87.25%   87.29%   +0.03%     
==========================================
  Files         136      136              
  Lines        8037     8043       +6     
  Branches     1974     1975       +1     
==========================================
+ Hits         7013     7021       +8     
  Misses        601      601              
+ Partials      423      421       -2

Impacted Files	Coverage Δ
...c/cfnlint/rules/resources/properties/Properties.py	76.58% <64.1%> (+1.71%)	⬆️
src/cfnlint/rules/__init__.py	86.85% <0%> (ø)	⬆️

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