lstab: Update expiration date

[mich181189]

The table is still valid, so update the expiration date

[oittaa]

Probably could be updated to further in the future.

Paris, 07 July 2025
...
NO leap second will be introduced at the end of December 2025.

https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat