Improve LDAP unit tests

This MR improves LDAP tests by mixing the output from slapd with the output of the tests:

$ DEBUG=1 LLNGTESTLDAP=1 prove t/21-Auth-LDAP-attributes.t

...
[Wed Jul 17 18:10:01 2024] [debug] Processing checkUnauthLogout
[Wed Jul 17 18:10:01 2024] [debug] Processing restoreArgs
[Wed Jul 17 18:10:01 2024] [debug] Processing controlUrl
[Wed Jul 17 18:10:01 2024] [debug] Processing extractFormInfo
[Wed Jul 17 18:10:01 2024] [debug] Processing getUser
6697ecd9.0c1a2e92 0x7f7f691fe6c0 conn=1001 op=5 SRCH base="" scope=0 deref=2 filter="(objectClass=*)"
6697ecd9.0c1a69c1 0x7f7f691fe6c0 conn=1001 op=5 SRCH attr=supportedLDAPVersion
6697ecd9.0c1b0223 0x7f7f691fe6c0 conn=1001 op=5 SEARCH RESULT tag=101 err=0 qtime=0.000008 etime=0.000070 nentries=1 text=
6697ecd9.0c1f5a17 0x7f7f691fe6c0 conn=1001 op=6 SRCH base="" scope=0 deref=2 filter="(objectClass=*)"
6697ecd9.0c1f713e 0x7f7f691fe6c0 conn=1001 op=6 SRCH attr=supportedLDAPVersion
6697ecd9.0c1fef98 0x7f7f691fe6c0 conn=1001 op=6 SEARCH RESULT tag=101 err=0 qtime=0.000005 etime=0.000046 nentries=1 text=
6697ecd9.0c2516ca 0x7f7f691fe6c0 conn=1001 op=7 BIND anonymous mech=implicit bind_ssf=0 ssf=71
6697ecd9.0c255e8b 0x7f7f691fe6c0 conn=1001 op=7 BIND dn="cn=admin,dc=example,dc=com" method=128
6697ecd9.0c2584c6 0x7f7f691fe6c0 conn=1001 op=7 BIND dn="cn=admin,dc=example,dc=com" mech=SIMPLE bind_ssf=0 ssf=71
6697ecd9.0c25ae68 0x7f7f691fe6c0 conn=1001 op=7 RESULT tag=97 err=0 qtime=0.000006 etime=0.000046 text=
6697ecd9.0c29f6cc 0x7f7f691fe6c0 conn=1001 op=8 SRCH base="ou=users,dc=example,dc=com" scope=2 deref=2 filter="(&(uid=russian)(objectClass=inetOrgPerson))"
6697ecd9.0c2a1d65 0x7f7f691fe6c0 conn=1001 op=8 SRCH attr=mail cn uid roomNumber displayName cn
6697ecd9.0c2aac8a 0x7f7f691fe6c0 conn=1001 op=8 SEARCH RESULT tag=101 err=0 qtime=0.000006 etime=0.000067 nentries=1 text=
[Wed Jul 17 18:10:01 2024] [debug] Processing authenticate
...