docs: Replace links in source

[loloicci]

Closes: #116

Description

replace links referring CosmWasm in source with links to ours.

Checklist:

• [x] I followed the contributing guidelines.
• [x] I have updated the documentation accordingly.
• [ ] I have added tests to cover my changes. (Not Needed)

[whylee259]

@loloicci There still exists lots of referring to the develop branch (lfb-sdk/blob/develop/) in this changes.