fix: use 'go env GOROOT' when GOROOT env is missing

Author: icholy

packages/@cdktf/hcl-tools/prebuild.sh

@@ -4,6 +4,8 @@
 
 set -euo pipefail
 
+GOROOT="${GOROOT:-$(go env GOROOT)}"
+
 if [[ -z "${GOROOT-}" ]]; then
   echo "GOROOT environment variable needs to be set!"
   exit 1

packages/@cdktf/hcl2json/prebuild.sh

@@ -4,6 +4,8 @@
 
 set -euo pipefail
 
+GOROOT="${GOROOT:-$(go env GOROOT)}"
+
 if [[ -z "${GOROOT-}" ]]; then
   echo "GOROOT environment variable needs to be set!"
   exit 1