Fix h2-console not accessible from menu.

[mshima]

Workaround undertow by adding a trailing / to h2-console link.

Fixes #14406

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[VergilSkye]

any solution to a generate project? I already made some custom modifications and i wish not to loose. Should i download this branch and regenerate the same project? Thanks for you work @mshima

I saw how to fixes, sorry to bother