pgsql: Use float8 datatype for percentiles in pg_walinspect stat functi

Use float8 datatype for percentiles in pg_walinspect stat functions

pg_walinspect uses datatype double (double precision floating point
number) for WAL stats percentile calculations and expose them via
float4 (single precision floating point number), which an unnecessary
loss of precision and confusing. Even though, it's harmless that way,
let's use float8 (double precision floating-point number) to be in
sync with what pg_walinspect does internally and what it exposes to
the users. This seems to be the pattern used elsewhere in the code.

Reported-by: Peter Eisentraut
Author: Bharath Rupireddy
Reviewed-by: Peter Eisentraut
Discussion: https://www.postgresql.org/message-id/36ee692b-232f-0484-ce94-dc39d82021ad%40enterprisedb.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/57796a0f15f8fd3c908aa885a7ebb8ae47ce9880

Modified Files
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contrib/pg_walinspect/pg_walinspect--1.0.sql | 16 ++++++++--------
contrib/pg_walinspect/pg_walinspect.c | 8 ++++----
doc/src/sgml/pgwalinspect.sgml | 16 ++++++++--------
3 files changed, 20 insertions(+), 20 deletions(-)