add: get ssm-parameter

[aaroniscode]

Issue #, if available:

Description of changes:
Add get ssm-parameter

Example

eksdemo get ssm-param /aws/service/neuron
+--------+--------------------------------------------------------------------------+-----------------------+
|  Age   |                                   Name                                   |         Value         |
+--------+--------------------------------------------------------------------------+-----------------------+
| 2 days | /aws/service/neuron/dlami/base/amazon-linux-2/latest/image_id            | ami-0e2d585f846ff29f6 |
| 2 days | /aws/service/neuron/dlami/base/ubuntu-20.04/latest/image_id              | ami-02aed491b5681c49e |
| 2 days | /aws/service/neuron/dlami/multi-framework/ubuntu-22.04/latest/image_id   | ami-07f9e2ccc9f0f4103 |
| 2 days | /aws/service/neuron/dlami/pytorch-1.13/amazon-linux-2/latest/image_id    | ami-001b12be6fb25e9ae |
| 1 week | /aws/service/neuron/dlami/pytorch-1.13/ubuntu-20.04/latest/image_id      | ami-03a805134c1a6c2e3 |
| 2 days | /aws/service/neuron/dlami/tensorflow-2.10/amazon-linux-2/latest/image_id | ami-04261454d107aa12e |
| 2 days | /aws/service/neuron/dlami/tensorflow-2.10/ubuntu-20.04/latest/image_id   | ami-09af131c9f79d84ab |
+--------+--------------------------------------------------------------------------+-----------------------+

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