Skip trace from nested exception constructors

[mvorisek]

Resulting trace is equal as copying this code from the base Exception class:

$this->trace2 = debug_backtrace(DEBUG_BACKTRACE_PROVIDE_OBJECT);

to the extended Exception classes.

With this PR, the trace is reduced properly without any need for code duplication.

[codecov]

Codecov Report

Merging #188 into develop will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@              Coverage Diff              @@
##             develop     #188      +/-   ##
=============================================
+ Coverage      96.97%   96.99%   +0.02%     
- Complexity       444      451       +7     
=============================================
  Files             24       24              
  Lines           1057     1065       +8     
=============================================
+ Hits            1025     1033       +8     
  Misses            32       32              

Impacted Files	Coverage Δ	Complexity Δ
src/Exception.php	100.00% <100.00%> (ø)	24.00 <0.00> (+7.00)

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[DarkSide666]

Looks fine with me.