Support optional query params in routing configuration

[agubler]

Type: feature

The following has been addressed in the PR:

• There is a related issue
• All code has been formatted with prettier as per the readme code style guidelines
• Unit or Functional tests are included in the PR

Description:

At the moment all query params defined in the routing configuration are considered mandatory, however there are times where a query params is optional but still need the router to generate the link correctly (depending on if the optional query param value is passed).

This changes adds a new ? indicator if a query param is to be considered optional:

{
    path: 'my/routes/path?{requiredQueryParam}&{optionalQueryParam?}'
}

The ? before the closing brace tells the router that the param is not required.

Resolves #508

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[codecov]

Codecov Report

Merging #901 (0259f6b) into master (ccaedb3) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #901      +/-   ##
==========================================
+ Coverage   94.59%   94.60%   +0.01%     
==========================================
  Files         127      127              
  Lines        8137     8139       +2     
  Branches     1901     1900       -1     
==========================================
+ Hits         7697     7700       +3     
+ Misses        440      439       -1     

Impacted Files	Coverage Δ
src/routing/Router.ts	100.00% <100.00%> (+0.45%)	⬆️

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