Merge bitcoindevkit/bdk#1978: ci: automated update to rustc 1.87.0

54e2b533a261ade79bfc6e17215ddde22c5f3248 ci: automated update to rustc 1.87.0 (Github Action)

Pull request description:

  Automated update to Github CI workflow `cont_integration.yml` by [create-pull-request](https://github.com/peter-evans/create-pull-request) GitHub action

ACKs for top commit:
  ValuedMammal:
    ACK 54e2b533a261ade79bfc6e17215ddde22c5f3248
  notmandatory:
    ACK 54e2b533a261ade79bfc6e17215ddde22c5f3248

Tree-SHA512: ead615e82de3f30980733c85271b9fc85644705750fbb4a1d6812831923da3370292bd7864e5ecc1b4ac182ad0d6ff22a861669a9cda7bbb1d9dc414abf82954