opt: (DEBUG) don't prune cols for delete

This change makes it so the PruneMutationReturnCols norm rule
doesn't apply to the DELETE operator. This is because, DELETE isn't
playing well with it right now. I suspect it's because of the way
the optbuilder creates projections over the DELETE mutation.

Release note: None

pkg/sql/opt/exec/execbuilder/testdata/delete

@@ -142,15 +142,18 @@ count           ·         ·
 ·               spans     ALL
 ·               limit     10
 
+# TODO(andyk): Prune columns so that index-join is not necessary.
 query TTT
 EXPLAIN DELETE FROM indexed WHERE value = 5 LIMIT 10 RETURNING id
 ----
-render               ·         ·
- └── run             ·         ·
-      └── delete     ·         ·
-           │         from      indexed
-           │         strategy  deleter
-           └── scan  ·         ·
-·                    table     indexed@indexed_value_idx
-·                    spans     /5-/6
-·                    limit     10
+render                     ·         ·
+ └── run                   ·         ·
+      └── delete           ·         ·
+           │               from      indexed
+           │               strategy  deleter
+           └── index-join  ·         ·
+                │          table     indexed@primary
+                └── scan   ·         ·
+·                          table     indexed@indexed_value_idx
+·                          spans     /5-/6
+·                          limit     10

pkg/sql/opt/exec/execbuilder/testdata/orderby

@@ -502,7 +502,7 @@ render               ·         ·          (b)        ·
       └── delete     ·         ·          (a, b, c)  ·
            │         from      t          ·          ·
            │         strategy  deleter    ·          ·
-           └── scan  ·         ·          (a, b)     ·
+           └── scan  ·         ·          (a, b, c)  ·
 ·                    table     t@primary  ·          ·
 ·                    spans     /3-/3/#    ·          ·
 

pkg/sql/opt/norm/rules/prune_cols.opt

@@ -469,7 +469,7 @@
 # conservative with the fetch columns.
 [PruneMutationReturnCols, Normalize]
 (Project
-    $input: (Insert | Update | Upsert | Delete
+    $input: (Insert | Update | Upsert
         $innerInput:*
         $checks:*
         $mutationPrivate:* & (CanPruneMutationReturnCols $mutationPrivate))

pkg/sql/opt/norm/testdata/rules/prune_cols

@@ -1879,25 +1879,26 @@ delete mutation
       ├── key: (6)
       └── fd: (6)-->(7,9,10)
 
-# Prune all columns not needed by the RETURNING clause.
+# TODO(ridwanmsharif): Fix PruneMutationReturnCols with DELETE.
 # TODO(andyk): Need to prune output columns.
-opt expect=(PruneMutationFetchCols,PruneMutationInputCols)
+opt expect-not=(PruneMutationFetchCols,PruneMutationInputCols)
 DELETE FROM a RETURNING k, s
 ----
 project
  ├── columns: k:1(int!null) s:4(string)
  ├── side-effects, mutations
+ ├── key: (1)
  ├── fd: (1)-->(4)
  └── delete a
       ├── columns: k:1(int!null) i:2(int) f:3(float) s:4(string)
-      ├── fetch columns: k:5(int) s:8(string)
+      ├── fetch columns: k:5(int) i:6(int) f:7(float) s:8(string)
       ├── side-effects, mutations
-      ├── key: (1-3)
-      ├── fd: (1)-->(4)
+      ├── key: (1)
+      ├── fd: (1)-->(2-4)
       └── scan a
-           ├── columns: k:5(int!null) s:8(string)
+           ├── columns: k:5(int!null) i:6(int) f:7(float) s:8(string)
            ├── key: (5)
-           └── fd: (5)-->(8)
+           └── fd: (5)-->(6-8)
 
 # Prune secondary family column not needed for the update.
 opt expect=(PruneMutationFetchCols,PruneMutationInputCols)