feat(logout): add logout token to browser response

[aeneasr]

Related issue(s)

Checklist

• I have read the contributing guidelines.
• I am following the
  contributing code guidelines.
• I have read the security policy.
• I confirm that this pull request does not address a security
  vulnerability. If this pull request addresses a security. vulnerability, I
  confirm that I got green light (please contact
  security@ory.sh) from the maintainers to push
  the changes.
• I have added tests that prove my fix is effective or that my feature
  works.
• I have added or changed the documentation.

Further Comments

[codecov]

Codecov Report

Merging #1758 (038d268) into master (d614f2a) will increase coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #1758      +/-   ##
==========================================
+ Coverage   74.10%   74.12%   +0.01%     
==========================================
  Files         260      260              
  Lines       12714    12715       +1     
==========================================
+ Hits         9422     9425       +3     
+ Misses       2667     2666       -1     
+ Partials      625      624       -1     

Impacted Files	Coverage Δ
selfservice/flow/logout/handler.go	83.58% <100.00%> (+0.24%)	⬆️
persistence/sql/persister_courier.go	88.33% <0.00%> (+3.33%)	⬆️

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