http3: use the master branch of GnuTLS for testing

Closes #6235

docs/HTTP3.md

@@ -55,7 +55,7 @@ Build ngtcp2
      % git clone https://github.com/ngtcp2/ngtcp2
      % cd ngtcp2
      % autoreconf -i
-     % ./configure PKG_CONFIG_PATH=<somewhere1>/lib/pkgconfig:<somewhere2>/lib/pkgconfig LDFLAGS="-Wl,-rpath,<somewhere1>/lib" --prefix=<somewhere3>
+     % ./configure PKG_CONFIG_PATH=<somewhere1>/lib/pkgconfig:<somewhere2>/lib/pkgconfig LDFLAGS="-Wl,-rpath,<somewhere1>/lib" --prefix=<somewhere3> --enable-lib-only
      % make
      % make install
 
@@ -70,9 +70,9 @@ Build curl
 
 ## Build with GnuTLS
 
-Build (patched) GnuTLS
+Build GnuTLS
 
-     % git clone --depth 1 -b tmp-quic https://gitlab.com/gnutls/gnutls.git
+     % git clone --depth 1 https://gitlab.com/gnutls/gnutls.git
      % cd gnutls
      % ./bootstrap
      % ./configure --disable-doc --prefix=<somewhere1>
@@ -95,7 +95,7 @@ Build ngtcp2
      % git clone https://github.com/ngtcp2/ngtcp2
      % cd ngtcp2
      % autoreconf -i
-     % ./configure PKG_CONFIG_PATH=<somewhere1>/lib/pkgconfig:<somewhere2>/lib/pkgconfig LDFLAGS="-Wl,-rpath,<somewhere1>/lib" --prefix=<somewhere3>
+     % ./configure PKG_CONFIG_PATH=<somewhere1>/lib/pkgconfig:<somewhere2>/lib/pkgconfig LDFLAGS="-Wl,-rpath,<somewhere1>/lib" --prefix=<somewhere3> --enable-lib-only
      % make
      % make install
 

scripts/travis/before_script.sh

@@ -35,7 +35,7 @@ if [ "$NGTCP2" = yes ]; then
     make install
 
     cd $HOME
-    git clone --depth 1 -b tmp-quic https://gitlab.com/gnutls/gnutls.git pgtls
+    git clone --depth 1 https://gitlab.com/gnutls/gnutls.git pgtls
     cd pgtls
     ./bootstrap
     ./configure PKG_CONFIG_PATH=$HOME/ngbuild/lib/pkgconfig LDFLAGS="-Wl,-rpath,$HOME/ngbuild/lib" --with-included-libtasn1 --with-included-unistring --disable-guile --disable-doc --prefix=$HOME/ngbuild