uclient: update to Git HEAD (2026-02-13)

uclient: update to Git HEAD (2026-02-13)

63413daa8760 uclient-http: fix HTTP authentication after deferred header processing
4fa6fae02f74 uclient-fetch: Extract opt_post variable
8df3120639a4 uclient-fetch: Use HEAD for --spider
0392dfc8e8c4 uclient-fetch: Support of --method, --body-data and --body-file
115c92824b6d uclient-fetch: add OPTIONS request type
a1531e89f6c2 uclient-fetch: support for WebDAV methods

Fixes: https://github.com/openwrt/uclient/issues/14
Signed-off-by: Felix Fietkau <nbd@nbd.name>