[master] f8974400e circleci: Escape spaces instead of quoting them

[Dridi Boukelmoune]

commit f8974400e43e973811f54643d35cc667a5b94efe
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Mon Sep 20 13:23:33 2021 +0200

    circleci: Escape spaces instead of quoting them
    
    It turns out, in addition to beeing enclosed inside sh -c '...' the
    CFLAGS may also be nested inside "double" quotes.

diff --git a/.circleci/config.yml b/.circleci/config.yml
index 2cb0c96de..01534fc90 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -365,7 +365,7 @@ workflows:
           name: distcheck_ubuntu_bionic
           dist: ubuntu
           release: bionic
-          extra_conf: CFLAGS="-g -O2 -m32"
+          extra_conf: CFLAGS=-g\ -O2\ -m32
       - distcheck:
           name: distcheck_alpine
           dist: alpine