Per slide transition ignored

Describe the bug

If I set a transition propriety in the frontmatter of a slide, the transition will be ignored and the default one (set in the initial page frontmatter) will play.

Minimal reproduction style.css

.my-transition-enter-active,
.my-transition-leave-active {
    transition: opacity 0.5s ease;
}

.my-transition-enter-from,
.my-transition-leave-to {
    opacity: 0;
}

slides.md

---
theme: seriph
# transition: fade-out
mdc: true
---

# Test slide

---

# Another slide

---
transition: my-transition
---

# Last slide

Steps to reproduce the behavior:

Just copy and paste the slides.md and style.css files into a new project and run

Environment

Slidev version: 0.49.16
Browser: Firefox and Chromium
OS: Linux

slidevjs / slidev

Per slide transition ignored #1752