fix(script): Remove visualization per literature type

For the time being removed the distinction between gray and white literature
as our sample did not lend itself to the dissection. May reintroduce later.

scoping_review.qmd

@@ -507,7 +507,7 @@ bib_df["literature"] = np.where(bib_df["pubtype"].str.contains("article", case=F
 bib_df["literature"] = bib_df["literature"].astype("category")
 
 # plot by year, distinguished by literature type
-ax = sns.countplot(bib_df, x="year", hue="literature")
+ax = sns.countplot(bib_df, x="year")
 ax.tick_params(axis='x', rotation=45)
 # ax.set_xlabel("")
 plt.tight_layout()