setup_pager: set GIT_PAGER_IN_USE

diff --git a/RelNotes b/RelNotes
index 09f5a7413c933a5778796a7b6b04499ac2c1a9f1..5a33236ce993853babae09bf228c9cd33b0ac808 120000 (symlink)
--- a/RelNotes
+++ b/RelNotes
@@ -1 +1 @@
-Documentation/RelNotes-1.5.1.2.txt
\ No newline at end of file
+Documentation/RelNotes/1.7.6.1.txt
\ No newline at end of file