[DOCS] Reserved words documentation lags behind the code

Crosschecked keywordMap from:
https://github.com/apache/impala/blob/master/fe/src/main/jflex/sql-scanner.flex

with upstream docs:
https://impala.apache.org/docs/build/html/topics/impala_reserved_words.html#reserved_words

As of 2022.11.30., keywords missing from docs:

&&
buckets
disable
enable
hudiparquet
iceberg
jsonfile
lexical
managedlocation
minus
norely
novalidate
||
orc
rely
rwstorage
sets
spec
storagehandler_uri
system_version
unset
validate
zorder 

Need to verify if some are already added, removed by being a builtin/being on whitelist and check whether they are Impala specific/SQL 2016/both to add to:
https://github.com/apache/impala/blob/master/docs/topics/impala_reserved_words.xml