[experiments][static][js][pannel] Fix URL generation on fork save

The original logic would get the first item of the experiment name
which matches the user name. However, the name variable in that case
contains the name of the fork, not the fully qualified name. To fix
that, directly use the username variable.
1 job for refactor_update_creation_api in 13 minutes and 58 seconds (queued for 2 seconds)
Status Job ID Name Coverage
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passed #197450
docker-build
build_linux_36

00:13:58

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