Fixed typo in SQL functions for SELECT SERVER_STATUS();

Fixed typo in Select documentation around _WDURATION.

Added the _wstart, _wend, and _wduration pseudocolumns to the documentation.

1. The CLI should come after Benchmark, otherwise it's confusing.
2. taos > shouldn't be in the command lines, otherwise users can copy and paste.
3. California.SanFrancisco doesn't match the current taosBenchmark
4. The Interval query was confusing, so I changed it to make more sense to me

1. The CLI should come after Benchmark, otherwise it's confusing.
2. taos > shouldn't be in the command lines, otherwise users can copy and paste.
3. California.SanFrancisco doesn't match the current taosBenchmark

Fixed broken link and added updated star count.

Co-authored-by: Shuduo Sang <sangshuduo@gmail.com>