Update to bdk v0.26.0

[rajarshimaitra]

Description

Upgrade to bdk v0.26.0

Notes to the reviewers

Checklists

All Submissions:

• [x] I've signed all my commits
• [x] I followed the contribution guidelines
• [x] I ran cargo fmt and cargo clippy before committing

[notmandatory]

Hey looks like you need do to a cargo fmt, missing a comma.

[rajarshimaitra]

Ah my bad.. Updated..

[notmandatory]

I updated bdk-reserves "update_bdk_026" branch with bdk rc.2.