Fix exec flags on getting-started scripts (#2878)

* Add `+x` to script source files
* Remove (unnecessary) `chmod` from docs

Author: dimas-b

getting-started/assets/cloud_providers/deploy-aws.sh

@@ -37,7 +37,6 @@ The requirements to run the script below are:
   * "sts:AssumeRole" on the same role as the Instance Profile role of the EC2 instance on which you are running this script. Additionally, you should ensure that the Instance Profile contains a trust policy that allows the role to trust itself to be assumed.
 
 ```shell
-chmod +x getting-started/assets/cloud_providers/deploy-aws.sh
 export ASSETS_PATH=$(pwd)/getting-started/assets/
 export CLIENT_ID=root
 export CLIENT_SECRET=s3cr3t

getting-started/assets/cloud_providers/deploy-azure.sh

@@ -32,7 +32,6 @@ The requirements to run the script below are:
 * Assign a System-Assigned Managed Identity to the Azure VM.
 
 ```shell
-chmod +x getting-started/assets/cloud_providers/deploy-azure.sh
 export ASSETS_PATH=$(pwd)/getting-started/assets/
 export CLIENT_ID=root
 export CLIENT_SECRET=s3cr3t

getting-started/assets/cloud_providers/deploy-gcp.sh

@@ -32,7 +32,6 @@ The requirements to run the script below are:
 * Ensure the VM's Principal has access to at least Read-only scope on Compute Engine: `compute.readonly`.
 
 ```shell
-chmod +x getting-started/assets/cloud_providers/deploy-gcp.sh
 export ASSETS_PATH=$(pwd)/getting-started/assets/
 export CLIENT_ID=root
 export CLIENT_SECRET=s3cr3t