qa/suites/rados/rest: run restful test on el8

For some reason the requests library has trouble connecting from
ubuntu 18.04.  I reproduced this locally on my 18.04 desktop, although
there it fails on the first API request instead of the last (as in QA).

In any case, this appears to be a client library problem.

Fixes: https://tracker.ceph.com/issues/43720
Signed-off-by: Sage Weil <sage@redhat.com>

diff --git a/qa/suites/rados/rest/centos_latest.yaml b/qa/suites/rados/rest/centos_latest.yaml
new file mode 120000 (symlink)
index 0000000..bd9854e
--- /dev/null
+++ b/qa/suites/rados/rest/centos_latest.yaml
@@ -0,0 +1 @@
+.qa/distros/supported/centos_latest.yaml
\ No newline at end of file

diff --git a/qa/suites/rados/rest/supported-random-distro$ b/qa/suites/rados/rest/supported-random-distro$
deleted file mode 120000 (symlink)
index 7cef21e..0000000
--- a/qa/suites/rados/rest/supported-random-distro$
+++ /dev/null
@@ -1 +0,0 @@
-../basic/supported-random-distro$
\ No newline at end of file