refactor(app): adapt no drugs message for gene detail

Due to change in #617 not only drugs that confirm with the
variant are shown.
The message should not be shown anyways due to changes in
the annotated drug data.

app/lib/l10n/app_en.arb

@@ -241,7 +241,7 @@
   "gene_page_phenotype_tooltip": "The phenotype describes the effect that your personal variant of this gene has on the enzyme it encodes.",
   "gene_page_affected_drugs": "Affected drugs",
   "gene_page_affected_drugs_tooltip": "The drugs listed here are affected by your variant of this gene.",
-  "gene_page_no_affected_drugs": "Your variant of this gene has no known effect on any drug.",
+  "gene_page_no_affected_drugs": "This gene has no known effect on any drug.",
   "gene_page_inhibitor_drugs": "Your results for this gene can be influenced if you are currently taking any of the following drugs:",
   "gene_page_further_inhibitor_drugs": "Your results for this gene can also be influenced if you are currently taking any of the following drugs:",
   "gene_page_activity_score": "Activity score",