Java library: set default value for commandType as "Text"

[lucyzhang929]

I tried to use Text as default but when I ran a Java function without the commandType specified, it threw an error:
Microsoft.Azure.WebJobs.Extensions.Sql: The type of the SQL attribute for an input binding must be either CommandType.Text for a direct SQL query, or CommandType.StoredProcedure for a stored procedure.

I'll leave it empty for now but can certainly revisit this.

Originally posted by @lucyzhang929 in #379 (comment)

[lucyzhang929]

I removed the commandType from some of our Java input binding samples and the functions worked as expected (tests also passed on ad hoc build pipeline). Not sure if there was a change in our extension that fixed this or a change in how the Java worker passes information to the sql extension.

Closing this issue since the error no longer appears.