chore: upgrade to rust 1.69 may be

[dzmitry-lahoda]

tried to add example on borsh schema, failed with:

error: package `borsh-derive v1.5.1` cannot be built because it requires rustc 1.67.0 or newer, while the currently active rustc version is 1.66.0
Either upgrade to rustc 1.67.0 or newer, or use
cargo update -p borsh-derive@1.5.1 --precise ver
where `ver` is the latest version of `borsh-derive` supporting rustc 1.66.0

[dzmitry-lahoda]

seems I cannot shell into with 1.67 too so easy:

info: installing component 'rustfmt'
error: package `toml_edit v0.21.1` cannot be built because it requires rustc 1.69 or newer, while the currently active rustc version is 1.67.0
Either upgrade to rustc 1.69 or newer, or use
cargo update -p toml_edit@0.21.1 --precise ver
where `ver` is the latest version of `toml_edit` supporting rustc 1.67.0

so in order to use rust-toolchain version as isolated shell seems need 1.69

[cberner]

What command are you running that hits that error? I'm able to run cargo fmt --all -- --check just fine

[dzmitry-lahoda]

ok, that works.

so only borsh 1.5+ has proper schema support, so adding example is possible iff 1.67

[cberner]

I don't want to increase the MSRV if it's only to support new examples