Test with sparse serialization, vertical merge and skip indices

tests/queries/0_stateless/03175_sparse_and_skip_index.reference

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+key	Sparse
+value	Sparse
+1000
+1

tests/queries/0_stateless/03175_sparse_and_skip_index.sql

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+DROP TABLE IF EXISTS t_bloom_filter;
+CREATE TABLE t_bloom_filter(
+  key UInt64,
+  value UInt64,
+
+  INDEX key_bf key TYPE bloom_filter(0.01) GRANULARITY 2147483648, -- bloom filter on sorting key column
+  INDEX value_bf value TYPE bloom_filter(0.01) GRANULARITY 2147483648  -- bloom filter on no-sorting column
+) ENGINE=MergeTree ORDER BY key
+SETTINGS
+    -- settings to trigger sparse serialization and vertical merge
+    ratio_of_defaults_for_sparse_serialization = 0.0
+    ,vertical_merge_algorithm_min_rows_to_activate = 1
+    ,vertical_merge_algorithm_min_columns_to_activate = 1
+    ,allow_vertical_merges_from_compact_to_wide_parts = 1
+    ,min_bytes_for_wide_part=0
+;
+
+SYSTEM STOP MERGES t_bloom_filter;
+
+-- Create at least one part
+INSERT INTO t_bloom_filter
+SELECT
+    number % 100 as key, -- 100 unique keys
+    rand() % 100 as value -- 100 unique values
+FROM numbers(50_000);
+
+-- And another part
+INSERT INTO t_bloom_filter
+SELECT
+    number % 100 as key, -- 100 unique keys
+    rand() % 100 as value -- 100 unique values
+FROM numbers(50_000, 50_000);
+
+SYSTEM START MERGES t_bloom_filter;
+
+-- Merge everything into a single part
+OPTIMIZE TABLE t_bloom_filter FINAL;
+
+-- Check sparse serialization
+SELECT column, serialization_kind FROM system.parts_columns WHERE database = currentDatabase() AND table = 't_bloom_filter' AND active ORDER BY column;
+
+SELECT COUNT() FROM t_bloom_filter WHERE key = 1;
+
+-- Check bloom filter non-zero size
+SELECT COUNT() FROM system.parts WHERE database = currentDatabase() AND table = 't_bloom_filter' AND secondary_indices_uncompressed_bytes > 200 AND active;