Feat: Entity Api Implementation

[ViragJain3010]

1. Created a entity vendor, a menu link attendance, route /attending to show the listing of vendors.
2. Explored types to create a entity. More formally there are two types:

• Dynamic: We use variables to create, edit, load, etc. the entity types.
  $entity = \Drupal::entityTypeManager()->getStorage($entity_type)->load(1);
• Static: In this we use hardCoded values
  $node = Node::load(1);

3. Many other functions offered by entity API like loadMultiple, getQuery, Entity::save() etc.

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