Use AnnotationHub to access ensembldb

[skanwal]

Draft PR:

• added a function to create annotationhub project
• removed previous ensembl db approach

To discuss

• Issue with the get_ensembl_db not exported from namespace:RNAsum
  • Edit: building the package using Shift + Cmd + B resolved this issue
• https://github.com/umccr/RNAsum/compare/rnasum-rpackage...update/ensembldb?expand=1#diff-af320bd625a5540c1bc51132c02f62b898f4ed007f7eaefb65adc967f88d0f98R16 is I believe referring to ensembldb select. It is also mentioned in the vignette. Need to confirm if it's referring to another select method.

[skanwal]

@pdiakumis - as discussed in our 1-1 last week, moved database logic to R script and updated rmd as well.

[skanwal]

Tested locally on my machine and the code works with the rds file under inst/extdata/tx_gene_id_105.rds.

Comparing reports between rnasum-rpackage and update/ensembldb branches next.