Corrupted btree index on HEAD because of covering indexes

Applying: Add amcheck missing downlink tests.
Using index info to reconstruct a base tree...
M	contrib/amcheck/expected/check_btree.out
M	contrib/amcheck/sql/check_btree.sql
M	contrib/amcheck/verify_nbtree.c
Falling back to patching base and 3-way merge...
Auto-merging contrib/amcheck/verify_nbtree.c
CONFLICT (content): Merge conflict in contrib/amcheck/verify_nbtree.c
Auto-merging contrib/amcheck/sql/check_btree.sql
CONFLICT (content): Merge conflict in contrib/amcheck/sql/check_btree.sql
Auto-merging contrib/amcheck/expected/check_btree.out
CONFLICT (content): Merge conflict in contrib/amcheck/expected/check_btree.out
Patch failed at 0001 Add amcheck missing downlink tests.

error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config advice.mergeConflict false"