pgsql: Use nbtdesc "level" field name consistently.

Use nbtdesc "level" field name consistently.

The "lev" name that appeared in NEWROOT nbtree record desc output was
inconsistent with the symbol name from the underlying C struct. It was
also inconsistent with nbtdesc output for other nearby record types with
similar level fields.

Standardize on "level" to make everything consistent.

Follow-up to commit 1c453cfd.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2584639653eec13726a25d6ea8a4b42153185723

Modified Files
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src/backend/access/rmgrdesc/nbtdesc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)