fix: do not create route table when using flannel

[mkosieradzki]

Reason for Change:

Flannel uses VXLAN encapsulation... so using route table makes no sense...

Issue Fixed:

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:
Trivial and obvious low hanging fruit.

[welcome]

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[codecov]

Codecov Report

Merging #486 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master     #486   +/-   ##
=======================================
  Coverage   54.56%   54.56%           
=======================================
  Files          97       97           
  Lines       14622    14622           
=======================================
  Hits         7978     7978           
  Misses       5971     5971           
  Partials      673      673

[jackfrancis]

/lgtm

[acs-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: jackfrancis, mkosieradzki

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