server/release: use the manifest file from bin directory (#23290)

server/build/release.mk

@@ -134,8 +134,8 @@ else
 endif
 	cp ../NOTICE.txt $(DIST_PATH)
 	cp ../README.md $(DIST_PATH)
-	if [ -f ../manifest.txt ]; then \
+	if [ -f bin/manifest.txt ]; then \
-		cp ../manifest.txt $(DIST_PATH); \
+		cp bin/manifest.txt $(DIST_PATH); \
 	fi
 
 	@# Import Mattermost plugin public key