Add map shim to Outlet

[agubler]

Type: bug

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:

Adds missing Map shim to Outlet

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[codecov]

Codecov Report

Merging #860 (a9780c0) into master (e74d23b) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #860   +/-   ##
=======================================
  Coverage   94.71%   94.71%           
=======================================
  Files         127      127           
  Lines        8084     8084           
  Branches     1884     1884           
=======================================
  Hits         7657     7657           
  Misses        427      427           

Impacted Files	Coverage Δ
src/routing/Outlet.tsx	100.00% <ø> (ø)

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