Disable legacy-shell for the releng variant

Author: vector-of-bool

.evergreen/generated_configs/legacy-config.yml

@@ -9228,6 +9228,8 @@ buildvariants:
   - abi-compliance-check
 - name: releng
   display_name: '**Release Archive Creator'
+  expansions:
+    SKIP_LEGACY_SHELL: '1'
   run_on: ubuntu2204-small
   tasks:
   - make-release-archive

.evergreen/legacy_config_generator/evergreen_config_lib/variants.py

@@ -72,7 +72,10 @@ def days(n: int) -> int:
             "debug-compile-with-warnings",
             OD([("name", "build-and-test-with-toolchain"), ("distros", ["debian10-small"])]),
         ],
-        {},
+        {
+            # Disable the MongoDB legacy shell download, which is not available in 5.0 for u22
+            "SKIP_LEGACY_SHELL": "1"
+        },
     ),
     Variant(
         "clang34ubuntu",