chore: enforce that site icons are .svg (#8684)

Makefile

@@ -410,9 +410,14 @@ else
 endif
 .PHONY: fmt/shfmt
 
-lint: lint/shellcheck lint/go lint/ts lint/helm
+lint: lint/shellcheck lint/go lint/ts lint/helm lint/site-icons
 .PHONY: lint
 
+lint/site-icons:
+	./scripts/check_site_icons.sh
+
+.PHONY: lint/site-icons
+
 lint/ts:
 	cd site
 	yarn && yarn lint

scripts/check_site_icons.sh

@@ -0,0 +1,44 @@
+#!/bin/bash
+
+set -euo pipefail
+# shellcheck source=scripts/lib.sh
+source "$(dirname "${BASH_SOURCE[0]}")/lib.sh"
+cdroot
+
+cd site/static/icon
+
+# These exceptions are here for backwards compatibility. All new icons should
+# be SVG to minimize the size of our repo and our bundle.
+exceptions=(
+	"aws.png"
+	"azure.png"
+	"docker.png"
+	"do.png"
+	"gcp.png"
+	"k8s.png"
+)
+
+function is_exception() {
+	local value="$1"
+	shift
+	for item; do
+		[[ "$item" == "$value" ]] && return 0
+	done
+	return 1
+}
+
+for file in *; do
+	# Extract filename
+	filename=$(basename -- "$file")
+
+	# Check if the file is in the exception list
+	if is_exception "$filename" "${exceptions[@]}"; then
+		continue
+	fi
+
+	# If not an exception, check if it's an svg file
+	if [[ "$file" != *.svg ]]; then
+		echo "Found a non-svg file not in exception list: $file"
+		exit 1
+	fi
+done