feat: added .env.test.example and updated readme

.env.test.example

@@ -0,0 +1,4 @@
+INFISICAL_HOST=
+INFISICAL_UNIVERSAL_AUTH_CLIENT_ID=
+INFISICAL_UNIVERSAL_AUTH_CLIENT_SECRET=
+INFISICAL_TEST_ORG_ID=

README.md

@@ -1,6 +1,6 @@
-# Infisical Terraform Provider 
+# Infisical Terraform Provider
 
-# Usage 
+# Usage
 
 ```
 terraform {
@@ -39,7 +39,8 @@ output "single-secret" {
 }
 ```
 
-# Development  
+# Development
+
 Tutorials for creating Terraform providers can be found on the [HashiCorp Learn](https://learn.hashicorp.com/collections/terraform/providers-plugin-framework) platform. _Terraform Plugin Framework specific guides are titled accordingly._
 
 ## Requirements
@@ -55,9 +56,12 @@ To compile the provider, run `go install`. This will build the provider and put
 
 To generate or update documentation, run `go generate`.
 
-In order to run the full suite of Acceptance tests, run `make testacc`.
+## Testing
+
+In order to run the full suite of Acceptance tests
 
-*Note:* Acceptance tests create real resources, and often cost money to run.
+- Set the following environment variables or save them in a .env file at the root. You can refer to the [example environment variable](./.env.test.example).
+- Run the following command from root
 
 ```shell
 make testacc