pgsql: Fix contrib/sepgsql test policy to work with latest SELinux rele

Fix contrib/sepgsql test policy to work with latest SELinux releases.

As of Fedora 30, it seems that the system-provided macros for setting
up user privileges in SELinux policies don't grant the ability to read
/etc/passwd, as they formerly did. This restriction breaks psql
(which tries to use getpwuid() to obtain the user name it's running
under) and thereby the contrib/sepgsql regression test. Add explicit
specifications that we need the right to read /etc/passwd.

Mike Palmiotto, per a report from me. Back-patch to all supported
branches.

Discussion: https://postgr.es/m/23856.1563381159@sss.pgh.pa.us

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/5c3d47287fd7c76aa376d035695bffde6d59a7c8

Modified Files
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contrib/sepgsql/sepgsql-regtest.te | 11 +++++++++++
1 file changed, 11 insertions(+)