Update ssd1306 requirement from 0.8.4 to 0.9.0 in /examples/twi-ssd1306 (#487)

Updates the requirements on [ssd1306](https://github.com/rust-embedded-community/ssd1306) to permit the latest version.
- [Release notes](https://github.com/rust-embedded-community/ssd1306/releases)
- [Changelog](https://github.com/rust-embedded-community/ssd1306/blob/master/CHANGELOG.md)
- [Commits](rust-embedded-community/ssd1306@v0.8.4...v0.9.0)

---
updated-dependencies:
- dependency-name: ssd1306
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

examples/twi-ssd1306/Cargo.toml

@@ -10,7 +10,7 @@ publish = false
 
 [dependencies]
 cortex-m-rt = "0.7.0"
-ssd1306 = "0.8.4"
+ssd1306 = "0.9.0"
 embedded-graphics = "0.8.1"
 panic-semihosting = "0.6.0"