chore: update README.md

README.md

@@ -37,7 +37,7 @@ This Github Action is used to run Terraform plan for a single, Atmos-supported c
 >
 > <details>
 > <summary><strong>Watch demo of using Atmos with Terraform</strong></summary>
-> <img src="https://github.com/cloudposse/atmos/blob/master/docs/demo.gif?raw=true"/><br/>
+> <img src="https://github.com/cloudposse/atmos/blob/main/docs/demo.gif?raw=true"/><br/>
 > <i>Example of running <a href="https://atmos.tools"><code>atmos</code></a> to manage infrastructure from our <a href="https://atmos.tools/quick-start/">Quick Start</a> tutorial.</i>
 > </detalis>
 
@@ -420,6 +420,8 @@ Which would produce the same behavior as in `v1`, doing this:
 
 | Name | Description |
 |------|-------------|
+| plan\_file | Path to the terraform plan file |
+| plan\_json | Path to the terraform plan in JSON format |
 | summary | Summary |
 <!-- markdownlint-restore -->