Certain tildes causing Markdown strikethrough formatting in generated tutorials

[coffee-squirrel]

Examples of 2 ~ resulting in strikethrough formatting:

• https://github.com/aws-samples/sample-developer-tutorials/blob/982b965efccc3fa5f67fecece9824f28926c77bc/tuts/001-lightsail-gs/lightsail-gs.md#cost-considerations
• https://github.com/aws-samples/sample-developer-tutorials/blob/main/tuts/037-emr-gs/emr-gs.md#connect-to-your-cluster-optional (near the end of the section)

[mwunderl]

Thanks! I will fix these and update the instructions.

[mwunderl]

Fixed in #21