ci: pin minreq to 2.13.2, base64ct to 1.6.0 for MSRV

[luisschwab]

Description

• Pin minreq to 2.13.2 because 2.13.3 uses the unstable std::sync::LazyLock (ci: pin minreq to 2.13.2, base64ct to 1.6.0 for MSRV #1886 (comment)).
• Pin base64ct to 1.6.0 for MSRV.

Required for #1885 (ubuntu-24.04 on all CI workflows).

Checklists

All Submissions:

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

[ValuedMammal]

Looks like the same should be done for 1.75. We may also need to pin minreq to fix this

error[E0658]: use of unstable library feature 'once_cell'
  --> /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/minreq-2.13.3/src/connection.rs:22:16
   |
22 | static CONFIG: std::sync::LazyLock<Arc<ClientConfig>> = std::sync::LazyLock::new(|| {
   |                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #74465 <https://github.com/rust-lang/rust/issues/74465> for more information

error[E0658]: use of unstable library feature 'once_cell'
  --> /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/minreq-2.13.3/src/connection.rs:22:57
   |
22 | static CONFIG: std::sync::LazyLock<Arc<ClientConfig>> = std::sync::LazyLock::new(|| {
   |                                                         ^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #74465 <https://github.com/rust-lang/rust/issues/74465> for more information

error[E0658]: use of unstable library feature 'once_cell'
  --> /home/runner/.cargo/registry/src/github.com-1ecc6299db9ec823/minreq-2.13.3/src/connection.rs:22:57
   |
22 | static CONFIG: std::sync::LazyLock<Arc<ClientConfig>> = std::sync::LazyLock::new(|| {
   |                                                         ^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: see issue #74465 <https://github.com/rust-lang/rust/issues/74465> for more information

   Compiling hyper v0.14.32

[luisschwab]

@ValuedMammal done on #1888 .

[ValuedMammal]

@ValuedMammal done on #1888 .

These should be in the same PR before we can merge.

[luisschwab]

Done @ValuedMammal

[ValuedMammal]

Still missing the pin(s) for the 1.75 test in cont_integration.yml. The error is shown here https://github.com/bitcoindevkit/bdk/actions/runs/13801087038/job/38603518407

I know it's confusing because we're pinning deps in two places for different rust versions.

[luisschwab]

I know it's confusing because we're pinning deps in two places for different rust versions.

Now I understand what was going on. Both 1.63.0 and 1.75.0 required the same pins, but pin-msrv.sh only pins for 1.63.0.

[LagginTimes]

ACK a186f00

[ValuedMammal]

ACK a186f00