Clarify moment of barrier tape deduction

[leanderb]

from Discord rule-book-discussion-2022 channel:

4. Scoring in case of deduction in percentage (e.g. tape collision): It is probably meant to be a deduction of the total points at the end, but it could also be e.g. 5% of the points gained until the time of the tape collision

[marcomasa]

Requires much more overhead for refs. I would stick with the deduction of the total points. We could clarify that in the RB however.

[steup]

I suggest we use percentage points to indicate deduction and increases to ease computation and prevent these discussions.

[leanderb]

• deduction at the end TODO TC: clarify in rulebook

[leanderb]

"of the final points are deducted" already in the rulebook