tests: remove outdated tests

! required by cran as I dropped shinytest from Suggestes

Author: davidgohel

DESCRIPTION

@@ -1,7 +1,7 @@
 Type: Package
 Package: ggiraph
 Title: Make 'ggplot2' Graphics Interactive
-Version: 0.9.5
+Version: 0.9.6.001
 Authors@R: c(
     person("David", "Gohel", , "david.gohel@ardata.fr", role = c("aut", "cre")),
     person("Panagiotis", "Skintzos", , "sigmapi@posteo.net", role = "aut"),