b/360833010 disable punch and stat collectives

[jolivier23]

There appears to be a leak with punch and stat collectives so let's disable them by default. We can use the environment variable to test fixes and possibly revert this later.

Required-githooks: true

Change-Id: I21588d20416bd3f7c24cf56ef8e059216d654503

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[github-actions]

Errors are component not formatted correctly,Ticket number prefix incorrect,PR title is malformatted. See https://daosio.atlassian.net/wiki/spaces/DC/pages/11133911069/Commit+Comments,Unable to load ticket data
https://daosio.atlassian.net/browse/b/360833010

[mjmac]

minor nit: I really prefer to put some kind of tracker for these kinds of TODO/FIXME changes. e.g. /* FIXME b/360833010: Restore to OBJ_COLL_THD_MIN when leak fixed */

Even better, use a new bug that can be closed when the FIXME is reverted. We do that a lot in the control plane code. Makes it harder to forget when there's an open ticket that gets looked at during planning.