Fix match.arg() in tiledb_group_open

[cgiachalis]

closes #779

before:

uri <- tempfile()
tiledb_group_create(uri)

grp <- tiledb_group(uri) # Defaults to READ
grp <- tiledb_group_close(grp)

tiledb_group_open(grp)   # Should default to READ
#> Error in type != "MODIFY_EXCLUSIVE" || tiledb_version(TRUE) >= "2.12.0": 'length = 3' in coercion to 'logical(1)'

after:

tiledb_group_open(grp)
#> filee887faf6ad3 GROUP

[mojaveazure]

Hey @cgiachalis, thanks for catching this! Can you bump the development version in the DESCRIPTION and add a changelog item to NEWS.md before merging?

[cgiachalis]

That's done from my end! We're good to go..

[mojaveazure]

Awesome, thank you @cgiachalis!