bump x.y.z version to odd y following creation of RELEASE_3_20 branch

Author: lshep

DESCRIPTION

@@ -1,7 +1,7 @@
 Package: TabulaMurisSenisData
 Type: Package
 Title: Bulk and single-cell RNA-seq data from the Tabula Muris Senis project
-Version: 1.12.0
+Version: 1.13.0
 Authors@R: c(person("Charlotte", "Soneson", role = c("aut", "cre"), 
                     email = "charlottesoneson@gmail.com", 
                     comment = c(ORCID = "0000-0003-3833-2169")),