Auto merge of #139410 - Zoxc:fix-dep-graph-no-prev-map, r=oli-obk

Reuse the index from promoted nodes when coloring executed tasks

rust-lang/rust#138824 did not correctly handle the case where a dep node was promoted green, but later or concurrently executed. It resulted in multiple dep nodes being allocated to it. This fixes that by checking that the node was not previously green in the encoder lock.

This also fixes a race when forcing diagnostic nodes introduced in rust-lang/rust#138824.

rust-lang/rust#138824 should get reverted on beta.

This should fix #139110.

r? `@oli-obk`

Author: bors