[TF2] [Feature Request] update items_game to add dispenser_build_rate_multiplier attribute definition

[Drgregs-Marcus]

For years, the attribute teleporter_build_rate_multiplier has applied to both the teleporter and the dispenser. And, given its name, this is unintended. To fix this, a new attribute definition and translations would have to be added for dispenser_build_rate_multiplier, as well as the pull request [Here] being merged.

This should cause no conflicts, since teleporter_build_rate_multiplier has gone unused in any official capacity to this point.

Attribute Definition:

        "882"
        {
            "name"    "engineer dispenser build rate multiplier"
            "attribute_class"    "dispenser_build_rate_multiplier"
            "description_string"    "#Attrib_Dispenser_Build_Rate"
            "description_format"    "value_is_percentage"
            "hidden"    "0"
            "effect_type"    "positive"
            "stored_as_integer"    "0"
        }

Translation String:

"Attrib_Dispenser_Build_Rate"                "Dispenser build speed increased by %s1%"