Add lower_quantile (#254)

Co-authored-by: Evan Stanton <evanstanton@Evans-MBP.fritz.box>

contrib/lower_quantile/Dockerfile

@@ -0,0 +1,8 @@
+ARG PG_VERSION=15
+FROM quay.io/coredb/c-builder:pg${PG_VERSION}
+
+# Clone repository
+RUN git clone https://github.com/tvondra/lower_quantile.git
+
+RUN cd lower_quantile && \
+    make

contrib/lower_quantile/Trunk.toml

@@ -0,0 +1,19 @@
+[extension]
+name = "lower_quantile"
+version = "1.0.0"
+repository = "https://github.com/tvondra/lower_quantile"
+license = "BSD-2-Clause"
+description = "Provides lower_quantile aggregate function."
+documentation = "https://github.com/tvondra/lower_quantile"
+categories = ["analytics"]
+
+[build]
+postgres_version = "15"
+platform = "linux/amd64"
+dockerfile = "Dockerfile"
+install_command = """
+    cd lower_quantile && make install
+    set -x
+    mv /usr/local/pgsql/share/extension/* /usr/share/postgresql/15/extension
+    mv /usr/local/pgsql/lib/* /usr/lib/postgresql/15/lib
+    """