Merge #158817

158817: build: remove reference to nonexistent `local-mixed-25.3` directory r=rail a=rickystewart

Closes #158741.

Release note: none
Epic: none

Co-authored-by: Ricky Stewart <ricky@cockroachlabs.com>

Author: craig[bot]

build/teamcity/cockroach/nightlies/sqllogic_corpus_nightly_impl.sh

@@ -81,7 +81,7 @@ if [ $exit_status = 0 ]; then
 fi
 
 # Generate a corpus for all mixed version variants
-for config in local-mixed-25.3 local-mixed-25.4; do
+for config in local-mixed-25.4; do
   $BAZEL_BIN/pkg/cmd/bazci/bazci_/bazci test -- --config=ci \
       //pkg/sql/logictest/tests/$config/... \
       --test_arg=--declarative-corpus=$ARTIFACTS_DIR/corpus-mixed \