[wget2] Fix build by using gmp instead of mini-gmp

[github-actions[bot]]

rockdaboot is either the primary contact or is in the CCs list of projects/wget2.
rockdaboot has previously contributed to projects/wget2. The previous PR was #11343

[rockdaboot]

Does anyone have an idea why this fails?

#11 [ 7/15] RUN wget -qO- https://gmplib.org/download/gmp/gmp-6.3.0.tar.gz | tar -xz && mv gmp-* gmp
#11 2821.8 
#11 2821.8 gzip: stdin: unexpected end of file
#11 2821.8 tar: Child returned status 1
#11 2821.8 tar: Error is not recoverable: exiting now
#11 ERROR: process "/bin/sh -c wget -qO- https://gmplib.org/download/gmp/gmp-6.3.0.tar.gz | tar -xz && mv gmp-* gmp" did not complete successfully: exit code: 2

I ran it several times locally and do not see any error.

[UPDATE] It looks like the oss-fuzz IP addresses are blocked by the GMPLIB firewall (see https://gmplib.org/security).