Rework the "by store" X509_LOOKUP method to open the given URI early

Rework the "by store" X509_LOOKUP method to open the given URI early

The cached X509_LOOKUP method data is no longer just the URI, but now
includes the OSSL_STORE_CTX pointer, and required parameters to reopen
the URI at any time.  cache_objects() is modified to handle this, and
only (re)open the URI when it wasn't previously opened, or when it was
closed by an earlier call.

This way, we can call OSSL_STORE_open_ex() in by_store_ctrl_ex(), and
get to see possible errors when the URI is loaded.

This assumes that if the URI could be opened once, it can be opened
again.

Fixes #27461

Reviewed-by: David von Oheimb <david.von.oheimb@siemens.com>
Reviewed-by: Tomas Mraz <tomas@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/27550)