update regression matrix to include old k8s (#6974)

Author: vepatel

.github/workflows/regression.yml

@@ -52,13 +52,13 @@ jobs:
             | sed 's/^.\{1\}//' \
             | tr -d '\n')
           echo "k8s_latest=$kindest_latest" >> $GITHUB_OUTPUT
-          kindest_versions=$(curl -s "https://hub.docker.com/v2/repositories/kindest/node/tags" \
+          kindest_versions=$(curl -s "https://hub.docker.com/v2/repositories/kindest/node/tags/?page_size=50" \
             | grep -o '"name": *"[^"]*' \
             | grep -o '[^"]*$' \
             | grep -E '^v[0-9]+\.[0-9]+\.[0-9]+$' \
             | sort -rV \
             | awk -F. '!seen[$1"."$2]++' \
-            | head -n 7 \
+            | head -n 8 \
             | sort -V \
             | sed 's/v//g' \
             | sed 's/$//' \