Fix pg_textsearch install for new release artifact format

v0.6.1 ships tarballs with raw extension files instead of .deb
packages in .zip files. Update the install script to download the
tarball and copy .so/.sql/.control files to the correct directories.

Author: tjgreen42

build_scripts/shared_install.sh

@@ -418,15 +418,16 @@ install_pg_textsearch() {
             mkdir -p /build/pg_textsearch
             cd /build/pg_textsearch
 
-            artifact="pg-textsearch-${version}-pg${pg}-${arch}.zip"
+            artifact="pg_textsearch-pg${pg}-${version}.tar.gz"
             curl --silent \
                  --fail \
                  --location \
-                 --output artifact.zip \
+                 --output artifact.tar.gz \
                  "https://github.com/timescale/pg_textsearch/releases/download/${version}/${artifact}"
 
-            unzip artifact.zip
-            dpkg --install --log=/build/pg_textsearch/dpkg.log --admindir=/build/pg_textsearch/ --force-depends --force-not-root --force-overwrite pg-textsearch*.deb
+            tar xzf artifact.tar.gz
+            cp "pg${pg}/"*.so "/usr/lib/postgresql/${pg}/lib/"
+            cp "pg${pg}/"*.sql "pg${pg}/"*.control "/usr/share/postgresql/${pg}/extension/"
         )
         err=$?
         if [ $err -eq 0 ]; then