pgsql: Add regression tests for ALTER MATERIALIZED VIEW with tablespace

Add regression tests for ALTER MATERIALIZED VIEW with tablespaces

The clauses SET TABLESPACE and ALL IN TABLESPACE are supported in ALTER
MATERIALIZED VIEW for a long time, and they behave mostly like ALTER
TABLE by reusing the same code paths, but there were zero tests for
them.  This commit closes the gap with new tests in tablespace.sql.

Author: Yugo Nagata
Discussion: https://postgr.es/m/20220316133337.5dc9740abfa24c25ec9f67f5@sraoss.co.jp

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/ade2159bcdc18939d4e9b1773d12fe06cfcd201d

Modified Files
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src/test/regress/expected/tablespace.out | 16 +++++++++++++++-
src/test/regress/sql/tablespace.sql      |  8 ++++++++
2 files changed, 23 insertions(+), 1 deletion(-)