Added credentials chain support in AWS Athena Driver

**Is your feature request related to a problem? Please describe.**
The Cubejs Athena driver supports only environment based credentials for permanent credentials according to what I see in the code (i.e. access and secret keys only).
However, there are multiple ways to authenticate on AWS, including short-lived credentials that require not only access and security keys, but secret and session tokens.
Forcing users to create long-lived credentials on their AWS account to support development or deployment of CubeJS doesn't seem the best way to go.

**Describe the solution you'd like**
One solution is to modify the AthenaDriver credentials setup to use a credentials provider chain including the SharedIniFileCredentials:
```
const envCreds = new AWS.Credentials({
accessKeyId: process.env.CUBEJS_AWS_KEY,
secretAccessKey: process.env.CUBEJS_AWS_SECRET,
region: process.env.CUBEJS_AWS_REGION});
const ec2Credentials = new AWS.EC2MetadataCredentials();
const sharedCreds = new AWS.SharedIniFileCredentials({profile: process.env.CUBEJS_AWS_PROFILE});
const chain = new AWS.CredentialProviderChain();
chain.providers.push(sharedCreds);
chain.providers.push(ec2Credentials);
chain.providers.push(envCreds);

this.config = {
// accessKeyId: process.env.CUBEJS_AWS_KEY,
// secretAccessKey: process.env.CUBEJS_AWS_SECRET,
credentialProvider: chain,
```
This chain will try to acquire
* credentials from the user ~/.aws/credentials file using the CUBEJS_AWS_PROFILE profile
* credentials from the EC2 environment (when deployed on AWS, which means using the EC2 instance role)
* credentials from the process.env.CUBEJS_XXX vars as last fallback

**Describe alternatives you've considered**
None for now.

**Additional context**