MT#57563 add ngcp.timezone version column

* this column stores the currently used olson database timezone
  version

Change-Id: Ib26c0d731d7f378717ea399d3a9f06d5f033a596
(cherry picked from commit 55477004f8)

db_scripts/diff/15767.down

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+USE ngcp;
+
+ALTER TABLE timezone DROP COLUMN version;

db_scripts/diff/15767.up

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+USE ngcp;
+
+ALTER TABLE timezone ADD COLUMN version VARCHAR(32);