Add invalid node reference case to middleware tests

[mar1n3r0]

No description provided.

[codecov]

Codecov Report

Merging #20 into hotfix/middleware-by-path will not change coverage.
The diff coverage is n/a.

@@                    Coverage Diff                     @@
##           hotfix/middleware-by-path      #20   +/-   ##
==========================================================
  Coverage                      71.26%   71.26%           
==========================================================
  Files                             10       10           
  Lines                            515      515           
==========================================================
  Hits                             367      367           
  Misses                           134      134           
  Partials                          14       14

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