Add libzstd.so.1 to fluentbit container build

Dockerfile.fluentbit

@@ -115,6 +115,7 @@ RUN make -C build install
 
 FROM mcr.microsoft.com/cbl-mariner/distroless/base:2.0.${MARINER_VERSION}-amd64
 COPY --from=builder \
+    /lib/libzstd.so.1 \
     /lib/libsystemd.so.0 \
     /lib/liblzma.so.5 \
     /lib/liblz4.so.1 \