[tempest]remove min_compute_nodes conf

Tempest can autodetect the number of computes

Author: gibizer

zuul.d/projects.yaml

@@ -8,7 +8,6 @@
       cifmw_operator_build_golang_alt_ct: "quay.rdoproject.org/openstack-k8s-operators/golang:1.20"
       cifmw_tempest_tempestconf_profile:
           overrides:
-            compute.min_compute_nodes: 3
             compute-feature-enabled.vnc_console: true
             compute-feature-enabled.stable_rescue: true
             compute_feature_enabled.hostname_fqdn_sanitization: true