ci: fix shellcheck failure

[whylee259]

Closes: #XXX

Description

When run shellcheck CLI, some issue are raised.

docker run --rm -v $(pwd)/devtools:/devtools koalaman/shellcheck  /devtools/generate_changelog.sh

In /devtools/generate_changelog.sh line 11:
if ! command -v git-chglog &>/dev/null; then
                           ^---------^ SC3020: In POSIX sh, &> is undefined.

In /devtools/generate_changelog.sh line 12:
  if command -v docker &>/dev/null; then
                       ^---------^ SC3020: In POSIX sh, &> is undefined.

this pr fixes the above issues.

Motivation and context

How has this been tested?

Checklist:

• [x] I followed the contributing guidelines.
• [ ] I have updated the documentation accordingly.
• [ ] I have added tests to cover my changes.