Revert JSONPath default path value from $ to . under RESP3

[LiorKogan]

For the following commands, the path argument is optional.
Currently the default path value is . under RESP2 and $ under RESP3.

JSON.ARRLEN key [path]
JSON.ARRPOP key [FORMAT STRINGS|EXPAND1|EXPAND] [path [index]]
JSON.DEBUG MEMORY key [path]
JSON.DEL key [path]
JSON.GET key [INDENT indent] [NEWLINE newline] [SPACE space] [FORMAT STRINGS|EXPAND1|EXPAND] [path [path ...]]
JSON.OBJKEYS key [path…]
JSON.OBJLEN key [path]
JSON.STRAPPEND key [path] value
JSON.STRLEN key [path]
JSON.TYPE key [path…]

Due to many request we decided to revert the default path value to . under both RESP2 and RESP3.

One request: #1090

[ephraimfeldblum]

This has been attended to in #1143 . This issue can be closed.