pgsql: Fix over-aggressive sanity check in misc_sanity.sql.

Fix over-aggressive sanity check in misc_sanity.sql.

Fix thinko in commit 8be8510cf: it's okay to have dbid == 0 in normal
(non-pin) entries in pg_shdepend, because global objects such as
databases are entered that way. The test would pass so long as it
was run in a cluster containing no databases/tablespaces owned by,
or granted to, roles other than the bootstrap superuser. That's the
expected situation for "make check", but for "make installcheck", not
so much.

Reported by Ryan Murphy.

Discussion: https://postgr.es/m/CAHeEsBc6EQe0mxGBKDXAwJbntgfvoAd5MQC-5362SmC3Tng_6g@mail.gmail.com

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/df44405a0c5c725706317c1faa6e8a0760f17dcc

Modified Files
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src/test/regress/expected/misc_sanity.out | 2 +-
src/test/regress/sql/misc_sanity.sql | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)