Update to SPHT v0.23 release (#876)

Author: agriyakhetarpal

Makefile

@@ -10,7 +10,7 @@ help:   ## show this help
 	@grep -h "##" $(MAKEFILE_LIST) | grep -v grep | sed -e 's/\(.*\):.*##\(.*\)/    \1: \2/'
 
 prepare:
-	git submodule update --init
+	git submodule update --init --recursive
 	((python -c 'import yaml2ics' && pre-commit) > /dev/null 2>&1) || python -m pip install -q -r requirements.txt
 	test -f .git/hooks/pre-commit || pre-commit install
 

netlify.toml

@@ -1,5 +1,5 @@
 [build.environment]
-  HUGO_VERSION = "0.152.2"
+  HUGO_VERSION = "0.158.0"
   DART_SASS_VERSION = "1.93.2"
   DART_SASS_URL = "https://github.com/sass/dart-sass/releases/download/"