Make regression test load options from file for checkpoint (#7864)

Summary:
The regression_test.sh script checkpoints the DB directory before running db_bench on it. Specify the --try_load_options when creating the checkpoint in order to load options from the OPTIONS file.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7864

Test Plan: manually run db_bench on the checkpoint dir

Reviewed By: akankshamahajan15

Differential Revision: D25926960

Pulled By: anand1976

fbshipit-source-id: d3442ae24a7044b474dc80efc9c06bdc6ebe0388

tools/regression_test.sh

@@ -294,14 +294,14 @@ function build_checkpoint {
             db_index=$(basename $dir)
             echo "Building checkpoints: $ORIGIN_PATH/$db_index -> $DB_PATH/$db_index ..."
             $cmd_prefix $DB_BENCH_DIR/ldb checkpoint --checkpoint_dir=$DB_PATH/$db_index \
-                        --db=$ORIGIN_PATH/$db_index 2>&1
+                        --db=$ORIGIN_PATH/$db_index --try_load_options 2>&1
         done
     else
         # checkpoint cannot build in directory already exists
         $cmd_prefix rm -rf $DB_PATH
         echo "Building checkpoint: $ORIGIN_PATH -> $DB_PATH ..."
         $cmd_prefix $DB_BENCH_DIR/ldb checkpoint --checkpoint_dir=$DB_PATH \
-                    --db=$ORIGIN_PATH 2>&1
+                    --db=$ORIGIN_PATH --try_load_options 2>&1
     fi
 }