[epiphany] Fix a typo

[Michael Catanzaro <mcatanzaro src gnome org>]

commit a44738a048cac53ccdfc32fcc93c94129e97ea44
Author: Michael Catanzaro <mcatanzaro gnome org>
Date:   Mon Sep 28 15:22:47 2020 +0000

    Fix a typo

 third-party/pdfjs/README.epiphany | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
---
diff --git a/third-party/pdfjs/README.epiphany b/third-party/pdfjs/README.epiphany
index bb187e153..1fbba14a6 100644
--- a/third-party/pdfjs/README.epiphany
+++ b/third-party/pdfjs/README.epiphany
@@ -51,7 +51,7 @@ In _pushOrReplaceState early return before the window.history.xxx changes
 
 Here are two small changes for webkit specific layout:
 
-1. Ading:
+1. Adding:
 -webkit-appearance: none; to .dropdownToolbarButton > select {
 
 2. Adding: