Badly formatted line in Debian changelog

Fix wrong date format in debian/changelog:
 warning:     debian/changelog(l6): badly formatted trailer line

Change-Id: I6ba546ecb9e813bcabca65af2e3e823303a53625
Signed-off-by: Petri Ovaska <petri.ovaska@nokia.com>
diff --git a/debian/changelog.in b/debian/changelog.in
index 0291e29..8ecc598 100644
--- a/debian/changelog.in
+++ b/debian/changelog.in
@@ -3,7 +3,7 @@
   * Multiple DBAAS Redis Sentinel groups
   * New namespace (--ns) option in sdltool test-get-set -command
 
- -- Petri Ovaska <petri.ovaska@nokia.com>  Wed May 26 17:27:08 2021 +0300
+ -- Petri Ovaska <petri.ovaska@nokia.com>  Wed, 26 May 2021 17:27:08 +0300
 
 sdl (1.1.3-1) UNRELEASED; urgency=low