bundle.sh: accept more forms of a branch name

For GitHub, add the following branch name formats:
- https://github.com/OISF/libhtp/pull/123
- OISF/libhtp#123

scripts/bundle.sh

@@ -33,8 +33,22 @@ what="$1"
 
 # Transforms a branch name in the form of "pr/<NUMBER>" or
 # "mr/<NUMBER>" into a proper ref for GitHub or GitLab.
+
+# Transform a branch name to a ref.
+#
+# For GitHub the following formats are allowed:
+# - pr/123
+# - pull/123
+# - https://github.com/OISF/libhtp/pull/123
+# - OISF/libhtp#123
+#
+# For GibLab only the format "mr/123" is supported.
 transform_branch() {
-    pr=$(echo "${1}" | sed -n 's/^pr\/\([[:digit:]]\+\)$/\1/p')
+    pr=$(echo "${1}" | sed -n \
+        -e 's/^https:\/\/github.com\/OISF\/.*\/pull\/\([0-9]*\)$/\1/p' \
+	-e 's/^OISF\/.*#\([0-9]*\)$/\1/p' \
+	-e 's/^pull\/\([0-9]*\)$/\1/p' \
+        -e 's/^pr\/\([0-9]*\)$/\1/p')
     if [ "${pr}" ]; then
 	echo "refs/pull/${pr}/head"
 	return