[S3] Filter out disabled Region to avoid exception while creating bucket

Context:

Some of the region is disabled by default in AWS (https://docs.aws.amazon.com/general/latest/gr/rande-manage.html) and some of them is "special" region. So we cannot create a new bucket in these regions, but we are listing them in the Region list select field.

• Create new S3 bucket 
• Select one of the disabled regions such as : Middle East (Bahrain), Africa (Cape Town), Asia Pacific (Hong Kong), Europe (Milan) or AWS GovCloud
• Submit -> Throws exception due to AWS permission

Expected result:

• Should only list the regions which is enabled (potentially can create bucket)

• Document the known issues if we can't implement this because AWS SDK may not support to check it (how to check region see https://docs.aws.amazon.com/general/latest/gr/rande-manage.html - Section Describing your Regions using the AWS CLI)