Remove unnecessary TINC test.

There are plenty of tests for the case that some but not all partitions
have an index, in the "partition_pruning" pg_regress test case.

src/test/tinc/tincrepo/partitioning/partitionindexes/expected/neg_alter_tab_drop_idx_2.ans

--- @author prabhd
--- @modified 2013-08-01 12:00:00
--- @created 2013-08-01 12:00:00
--- @db_name ptidx
--- @tags partitionindexes
--- @negtest True
--- @description Negative tests ALTER TABLE, drop index
--- start_ignore
-DROP INDEX IF EXISTS idx1_1_prt_part4;
-DROP INDEX
--- end_ignore
-SELECT * FROM pt_lt_tab WHERE col2 = 35 ORDER BY col2,col3 LIMIT 5;
- col1 | col2 | col3  | col4 
-------+------+-------+------
-   35 |   35 | part4 | f
-(1 row)
-

src/test/tinc/tincrepo/partitioning/partitionindexes/sql/neg_alter_tab_drop_idx_2.sql

--- @author prabhd
--- @modified 2013-08-01 12:00:00
--- @created 2013-08-01 12:00:00
--- @db_name ptidx
--- @tags partitionindexes
--- @negtest True
--- @description Negative tests ALTER TABLE, drop index
--- start_ignore
-DROP INDEX IF EXISTS idx1_1_prt_part4;
--- end_ignore
-SELECT * FROM pt_lt_tab WHERE col2 = 35 ORDER BY col2,col3 LIMIT 5;

src/test/tinc/tincrepo/partitioning/partitionindexes/sql/neg_alter_tab_drop_idx_2_setup.sql

-DROP TABLE IF EXISTS pt_lt_tab;
-CREATE TABLE pt_lt_tab
-(
-  col1 int,
-  col2 decimal,
-  col3 text,
-  col4 bool
-  
-)
-distributed by (col1)
-partition by list(col2)
-(
-	partition part1 values(1,2,3,4,5,6,7,8,9,10),
-	partition part2 values(11,12,13,14,15,16,17,18,19,20),
-	partition part3 values(21,22,23,24,25,26,27,28,29,30),
-	partition part4 values(31,32,33,34,35,36,37,38,39,40),
-	partition part5 values(41,42,43,44,45,46,47,48,49,50),
-        default partition def
-);
-
-INSERT INTO pt_lt_tab SELECT i, i,'part1',True FROM generate_series(1,10)i;
-INSERT INTO pt_lt_tab SELECT i, i,'part2',True FROM generate_series(11,20)i;
-INSERT INTO pt_lt_tab SELECT i, i,'part3',False FROM generate_series(21,30)i;
-INSERT INTO pt_lt_tab SELECT i, i,'part4',False FROM generate_series(31,40)i;
-INSERT INTO pt_lt_tab SELECT i, i,'part5',False FROM generate_series(41,50)i;
-INSERT INTO pt_lt_tab SELECT i, i,'part5',False FROM generate_series(41,50)i;
-INSERT INTO pt_lt_tab SELECT i, i,'part6',False FROM generate_series(51,60)i;
-INSERT INTO pt_lt_tab VALUES(NULL,NULL,NULL,NULL);
-INSERT INTO pt_lt_tab VALUES(NULL,NULL,NULL,NULL);
-
-DROP INDEX IF EXISTS idx1;
-CREATE INDEX idx1 on pt_lt_tab(col2);
-ANALYZE pt_lt_tab;