Add a new pattern for NFS directories: /Volumes/net

Summary:
Add a new pattern for NFS directories: /Volumes/net to un-break macOS tests.  Without this,
mini-cluster data directories end up on NFS, leading to test failures.

Test Plan: Jenkins: skip

Reviewers: bogdan, robert, oleg, amitanand, sergei

Reviewed By: sergei

Subscribers: ybase

Differential Revision: https://phabricator.dev.yugabyte.com/D6371

build-support/common-build-env.sh

@@ -1605,7 +1605,7 @@ is_jenkins_phabricator_build() {
 
 # Check if we're using an NFS partition in YugaByte's build environment.
 is_src_root_on_nfs() {
-  if [[ $YB_SRC_ROOT =~ ^/(n|z|u|net)/ ]]; then
+  if [[ $YB_SRC_ROOT =~ ^/(n|z|u|net|Volumes/net)/ ]]; then
     return 0
   fi
   return 1