pgsql: Add accidentally omitted test to meson build file

Add accidentally omitted test to meson build file

01e2b7f0fd02a44e introduced a test that vacuum correctly removes tuples
older than OldestXmin. The same commit was backpatched on 14-16, but 16
is the only version with meson and the test was mistakenly left off of
the recovery test meson build file. Add it now.

Discussion: https://postgr.es/m/CAAKRu_bWmMjmqL%2BOZ2duEQ80u7cRvpsExLNZNjzk-pXX5skwMQ%40mail.gmail.com

Branch
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REL_16_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9d198f4d3e3bee1b2f392c1466728f6d19c89ada

Modified Files
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src/test/recovery/meson.build | 1 +
1 file changed, 1 insertion(+)