qa/crimson-rados: remove centos 8 symlinks

As we're trying to drop centos 8 from the distros we
test on these symlinks are now dead and need to be
cleaned up. In main, there was no replacement for
these symlinks (it just relies on the
crimson-supposted-all-distro dir for its distro)
so I'm just removing them here.

Signed-off-by: Adam King <adking@redhat.com>

diff --git a/qa/suites/crimson-rados/basic/centos_8.stream.yaml b/qa/suites/crimson-rados/basic/centos_8.stream.yaml
deleted file mode 120000 (symlink)
index 5dceec7..0000000
--- a/qa/suites/crimson-rados/basic/centos_8.stream.yaml
+++ /dev/null
@@ -1 +0,0 @@
-.qa/distros/supported/centos_8.stream.yaml
\ No newline at end of file

diff --git a/qa/suites/crimson-rados/rbd/centos_8.stream.yaml b/qa/suites/crimson-rados/rbd/centos_8.stream.yaml
deleted file mode 120000 (symlink)
index 5dceec7..0000000
--- a/qa/suites/crimson-rados/rbd/centos_8.stream.yaml
+++ /dev/null
@@ -1 +0,0 @@
-.qa/distros/supported/centos_8.stream.yaml
\ No newline at end of file

diff --git a/qa/suites/crimson-rados/thrash/centos_8.stream.yaml b/qa/suites/crimson-rados/thrash/centos_8.stream.yaml
deleted file mode 120000 (symlink)
index 5dceec7..0000000
--- a/qa/suites/crimson-rados/thrash/centos_8.stream.yaml
+++ /dev/null
@@ -1 +0,0 @@
-.qa/distros/supported/centos_8.stream.yaml
\ No newline at end of file