Speed Up COUNT(DISTINCT) for String Types by Inlining SipHash with 11.6% QPS Improvement in Query Q8

Speed up COUNT(DISTINCT) for String types by inlining SipHash. The performance experiments of OnTime on the ICX device (Intel Xeon Platinum 8380 CPU, 80 cores, 160 threads) show that this change could bring an improvement of 11.6% to the QPS of the query Q8 while having no impact on others. #52036 (Zhiguo Zhou).