fix: append to empty request array

[sweatybridge]

What kind of change does this PR introduce?

Bug fix

What is the new behavior?

follow up #3277

Additional context

Add any other context or screenshots.

[coveralls]

Pull Request Test Coverage Report for Build 13774747273

Details

• 0 of 1 (0.0%) changed or added relevant line in 1 file are covered.
• 8 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.04%) to 57.683%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
pkg/function/batch.go	0	1	0.0%

Files with Coverage Reduction	New Missed Lines	%
internal/debug/postgres.go	3	64.86%
internal/gen/keys/keys.go	5	12.9%

Totals
Change from base Build 13769617543:	-0.04%
Covered Lines:	7846
Relevant Lines:	13602

---

💛 - Coveralls