Use quiche string libraries in third_party/quic/core/qpack
gfe-relnote: n/a, no functional change
PiperOrigin-RevId: 285014753
Change-Id: I400c158ecab7cbc70666dd8a7651aaec249a5d2e
QUICHE (QUIC, Http/2, Etc) is Google‘s implementation of QUIC and related protocols. It powers Chromium as well as Google’s QUIC servers and some other projects.