pgsql: Move new SLRU buffers GUCs to a better place in postgresql.conf.

Move new SLRU buffers GUCs to a better place in postgresql.conf.sample

They were under "File Locations", which doesn't make sense.  Move them
to Resource Usage / Memory, which matches their categorization in the
source code and in the documentation.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/b6dbbaa3028f0da01cd4716f8d9c1c766b103cba

Modified Files
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src/backend/utils/misc/postgresql.conf.sample | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)