pgsql: meson: tests: Adjust with_icu/ZSTD env vars for pg_dump, pg_base

meson: tests: Adjust with_icu/ZSTD env vars for pg_dump, pg_basebackup

396d348b0 omitted adding with_icu to the pg_dump tests under
meson. Conversely, e6927270c exported ZSTD for pg_basebackup's tests, despite
pg_basebackup's ZSTD support not having any tests.

Reported-by: Justin Pryzby <pryzby@telsasoft.com>
Discussion: https://postgr.es/m/20230226225239.GL1653@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8bf826528ae9ff7a543a49c0dce665fa9ec542cb

Modified Files
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src/bin/pg_basebackup/meson.build | 2 +-
src/bin/pg_dump/meson.build       | 1 +
2 files changed, 2 insertions(+), 1 deletion(-)