pgsql: Restrict some cases in parsing numerics in jsonpath

Restrict some cases in parsing numerics in jsonpath

Jsonpath now accepts integers with leading zeroes and floats starting with
a dot. However, SQL standard requires to follow JSON specification, which
doesn't allow none of these cases. Our json[b] datatypes also restrict that.
So, restrict it in jsonpath altogether.

Author: Nikita Glukhov

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2e643501e5281ad5e0fa626dab1d51c1d38f639a

Modified Files
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src/backend/utils/adt/jsonpath_scan.l | 6 +-
src/test/regress/expected/jsonpath.out | 117 +++++++++++++++------------------
2 files changed, 55 insertions(+), 68 deletions(-)