Update Hugo to version 0.87.0

Dockerfile

@@ -9,9 +9,9 @@
 # to work around segmentation fault issues.
 FROM golang:1.13-alpine
 ARG HUGO=hugo
-ARG HUGO_VERSION=0.86.1
-ARG HUGO_SHA=1a8e8dbaf87ec8c4170819aed3f60e81d638836828b4bf886d6160c2e9752c4e
-ARG HUGO_EXTENDED_SHA=35c5e0b526c46781b66874854bca816338c8f48dbdacb0bb6e1ce6175ea0b649
+ARG HUGO_VERSION=0.87.0
+ARG HUGO_SHA=0d14003eb17c16ed83e465f754f3be11a2c74b9574258c81935a16822bcf3f0b
+ARG HUGO_EXTENDED_SHA=f216af92c06809c03981296f513ce54d3d690715d3c9fdfaff802d4a6759a260
 RUN set -eux && \
     case ${HUGO} in \
       *_extended) \