Setting the ANYVAR_SQL_STORE_FLUSH_ON_BATCHCTX_EXIT environment variable has no effect

[ehclark]

Setting the ANYVAR_SQL_STORE_FLUSH_ON_BATCHCTX_EXIT environment variable to false, no or 0 should cause the VCF annotation endpoint to return immediately instead of waiting for database updates to complete. Setting the environment variable has no effect.

The problem is that the environment variable value is passed to bool(), which converts to a boolean based on the whether the string is empty or not.