[CI] Build secp256k1 with endomorphism disabled

Summary:
Since endomorphism is now enabled by default, the
build-secp256k1-endomorphism is redundant with the build-secp256k1
config. This diff updates it to build-secp256k1-without-endomorphism
instead.

Test Plan:

./contrib/teamcity/build-configurations.py

build-secp256k1-without-endomorphism

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D8025