Stylistic and grammatical changes.

Stylistic and grammatical changes.

Minor grammatical changes.
Changed DESCRIBE to - For example "SELECT" cannot be abbreviated as "SEL" - since DESCRIBE can actually be abbreviated to DESC in TDengine.

Made a few stylistic and grammatical changes.

- Spelling
- rephrased sentences

Several changes:
-spelling
-reordering paragraphs for clarity
-rewrote some sentences
-added clarification for UDF being available across databases in an instance i.e. scope is not limited to a database when it is created.

fix(query): fix avg used in group by NULL value calculated as nan

fix(os): windows run shell case

feat: build submit blk by group id in rsma result

TD-15892

fix: set standby while create mnode

fix(sync) raftCfgPersist

fix(query): fix diff function result type to avoid overflow

fix(os): windows timezone error

fix:fix bound index error in schemaless

test: restore some case

TD-16068

fix: return mnode epset while master changed

fix(query): fix diff function param check

enh(sync) snapshot sender, receiver

test： add hyperloglog case to CI

test:modify paramerter

TD-16065

fix(query): set the gid for stream result.

TD-16067

TD-16066

feat: parser adapts asynchronous interface