Added ESP-IDF Template (#739)

Co-authored-by: Abdurrahmaan Iqbal <abdurriq@github.com>

Author: T0ng5

_data/collection-index.yml

@@ -1601,6 +1601,11 @@
   contact: https://github.com/zafnz/devcontainer-features/issues
   repository: https://github.com/zafnz/devcontainer-features
   ociReference: ghcr.io/zafnz/devcontainer-features
+- name: ESP-IDF Dev Container Templates
+  maintainer: T0ng5
+  contact: https://github.com/T0ng5/esp-idf/issues
+  repository: https://github.com/T0ng5/esp-idf
+  ociReference: ghcr.io/t0ng5/esp-idf
 - name: raine-works Dev Container Features
   maintainer: Raineworks
   contact: https://github.com/raine-works/devcontainer-features/issues