pgsql: Fix CREATE TABLE / LIKE with bigint identity column

Fix CREATE TABLE / LIKE with bigint identity column

CREATE TABLE / LIKE with a bigint identity column would fail on
platforms where long is 32 bits. Copying the sequence values used
makeInteger(), which would truncate the 64-bit sequence data to 32 bits.
To fix, use makeFloat() instead, like the parser. (This does not
actually make use of floats, but stores the values as strings.)

Bug: #15096
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/c32f44c4a5b27f5055600db1a7374a898f3681df

Modified Files
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src/backend/commands/sequence.c | 19 +++++++++++------
src/test/regress/expected/create_table_like.out | 28 ++++++++++++-------------
src/test/regress/sql/create_table_like.sql | 2 +-
3 files changed, 28 insertions(+), 21 deletions(-)