bitbucket-pipelines.yml: Change `make check` to `make distcheck`
Now that `make distcheck` should succeed, we can just use it as it
internally does `make check`. This patch changes the BitBucket
pipeline file to do so.
#
# Makefile.mingw
#
# Description: Makefile for win32 (mingw) version of libpurple
#
PIDGIN_TREE_TOP:=..
include $(PIDGIN_TREE_TOP)/libpurple/win32/global.mak