[BUG]: Duplication of branch 'unstable' in "benchmarksredisio" Grafana dashboard

[markovamaria]

Describe the bug
Branch "unstable is duplicating" in Dashboard.
1 - "unstable"
2 - "refs/heads/unstable"

Expected behavior
Data for 1 of 2 branches should be collected and represented on dashborad. Suggest "unstable" as this branch is presented in Redis repo.

Screenshots/CLI snippets

[filipecosta90]

Revise again in 1 month to check if the /ref/head/ is fully removed from latest data.
Currently we still have this data there ( at the start of previous month )