Add test to catch crash when creating extension in transaction and using operator in the same tx

[var77]

The database crash is happening if extension is being created in the same transaction when operator is used. Postgres failed to lookup the operator oid by name and crashes with segfault.

Here is the full backtrace of crash:

Program received signal SIGSEGV, Segmentation fault.
0x0000562e35e57874 in GetRealCmin (combocid=3) at combocid.c:282
282             return comboCids[combocid].cmin;
(gdb) bt
#0  0x0000562e35e57874 in GetRealCmin (combocid=3) at combocid.c:282
]#1  HeapTupleHeaderGetCmin (tup=tup@entry=0x7f7b521d0060) at combocid.c:112
#2  0x0000562e35a512b2 in HeapTupleSatisfiesMVCC (htup=0x1, htup=0x1, buffer=1, snapshot=0x562e37b81df8)
    at heapam_visibility.c:1013
#3  HeapTupleSatisfiesVisibility (tup=tup@entry=0x562e37b49608, snapshot=snapshot@entry=0x562e37b81df8,
    buffer=buffer@entry=1) at heapam_visibility.c:1771
#4  0x0000562e35a463f5 in heap_hot_search_buffer (tid=tid@entry=0x562e37b49728, relation=0x7f7b519fc350, buffer=1,
    snapshot=snapshot@entry=0x562e37b81df8, heapTuple=heapTuple@entry=0x562e37b49608,
    all_dead=all_dead@entry=0x7ffed209e087, first_call=true) at heapam.c:1764
#5  0x0000562e35a4de54 in heapam_index_fetch_tuple (scan=0x562e37b499f8, tid=0x562e37b49728,
    snapshot=0x562e37b81df8, slot=0x562e37b495b8, call_again=0x562e37b4972e, all_dead=0x7ffed209e087)
    at heapam_handler.c:143
#6  0x0000562e35a5bc4d in table_index_fetch_tuple (all_dead=0x7ffed209e087, call_again=0x562e37b4972e,
    slot=<optimized out>, snapshot=<optimized out>, tid=0x562e37b49728, scan=<optimized out>)
    at ../../../../src/include/access/tableam.h:1226
#7  index_fetch_heap (scan=0x562e37b496c8, slot=<optimized out>) at indexam.c:580
#8  0x0000562e35a5bd05 in index_getnext_slot (scan=0x562e37b496c8, direction=direction@entry=ForwardScanDirection,
    slot=0x562e37b495b8) at indexam.c:640
#9  0x0000562e35a5b187 in systable_getnext (sysscan=sysscan@entry=0x562e37b49568) at genam.c:511
#10 0x0000562e35e084fa in SearchCatCacheList (cache=0x562e37bb9280, nkeys=nkeys@entry=3, v1=140167779025004,
    v2=v2@entry=1007, v3=v3@entry=1007) at catcache.c:1639
#11 0x0000562e35e1991d in SearchSysCacheList (cacheId=cacheId@entry=37, nkeys=nkeys@entry=3, key1=<optimized out>,
    key2=key2@entry=1007, key3=key3@entry=1007) at syscache.c:1493
#12 0x0000562e35ac7371 in OpernameGetOprid (names=names@entry=0x562e37b49518, oprleft=oprleft@entry=1007,
    oprright=oprright@entry=1007) at namespace.c:1568
#13 0x0000562e35b09e31 in LookupOperName (pstate=0x0, opername=0x562e37b49518, oprleft=1007, oprright=1007,
    noError=<optimized out>, location=-1) at parse_oper.c:106
#14 0x00007f7b5aa91f91 in ldb_get_operator_oids () at /root/lantern/src/hooks/utils.c:14
#15 0x00007f7b5aa91e88 in post_parse_analyze_hook_with_operator_check (pstate=0x562e37b492d8, query=0x562e37b493e8,
    jstate=0x0) at /root/lantern/src/hooks/post_parse.c:173
#16 0x0000562e35ae42bc in parse_analyze_fixedparams (parseTree=parseTree@entry=0x562e37b49258,
    sourceText=sourceText@entry=0x562e37b48858 "END;", paramTypes=paramTypes@entry=0x0,
    numParams=numParams@entry=0, queryEnv=queryEnv@entry=0x0) at analyze.c:129
#17 0x0000562e35cfca1b in pg_analyze_and_rewrite_fixedparams (queryEnv=0x0, numParams=0, paramTypes=0x0,
    query_string=0x562e37b48858 "END;", parsetree=0x562e37b49258) at postgres.c:657
#18 exec_simple_query (query_string=0x562e37b48858 "END;") at postgres.c:1166
#19 0x0000562e35cfec25 in PostgresMain (dbname=<optimized out>, username=<optimized out>) at postgres.c:4593
#20 0x0000562e35c7f08d in BackendRun (port=0x562e37b7f2d0, port=0x562e37b7f2d0) at postmaster.c:4511
#21 BackendStartup (port=0x562e37b7f2d0) at postmaster.c:4239
#22 ServerLoop () at postmaster.c:1806
#23 0x0000562e35c7fff3 in PostmasterMain (argc=argc@entry=3, argv=argv@entry=0x562e37b44390) at postmaster.c:1478
#24 0x0000562e35a068ff in main (argc=3, argv=0x562e37b44390) at main.c:202

[github-actions]

Benchmarks

metric	old	new	pct change
recall (after create)	0.740	0.740	-
recall (after insert)	0.780	0.708	-9.23%
select bulk tps	489.926	485.972	-0.81%
select bulk latency (ms)	15.608	15.655	+0.30%
select bulk latency (stddev ms)	2.273	4.113	+80.95%
create latency (ms)	1189.657	1187.070	-0.22%
insert bulk tps	11.655	11.632	-0.20%
insert bulk latency (ms)	85.792	85.960	+0.20%
insert bulk latency (stddev ms)	3.262	3.178	-2.58%
disk usage (bytes)	6348800.000	6348800.000	-