pgsql: Add tests for bytea LIKE operator

Add tests for bytea LIKE operator

Add test coverage for the following operations, which were previously
not tested at all:

bytea LIKE bytea (bytealike)
bytea NOT LIKE bytea (byteanlike)
ESCAPE clause for the above (like_escape_bytea)

also

name NOT ILIKE text (nameicnlike)

Discussion: https://www.postgresql.org/message-id/flat/4d13563a-2c8d-fd91-20d5-e71b7a4eaa87%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/eb42110d952f8d1ad4049b8f2491e9dfba75ffed

Modified Files
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src/test/regress/expected/strings.out | 48 +++++++++++++++++++++++++++++++++++
src/test/regress/sql/strings.sql      | 12 +++++++++
2 files changed, 60 insertions(+)