starlette: add args to instrument_app docstring (#4014)

* fix: add args to instrument_app docstring in starlette

* Update docs-requirements.txt

* fix docs ci

Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>

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Signed-off-by: emdneto <9735060+emdneto@users.noreply.github.com>
Co-authored-by: Riccardo Magliocchetti <riccardo.magliocchetti@gmail.com>
Co-authored-by: emdneto <9735060+emdneto@users.noreply.github.com>