Release langchain-anthropic==0.1.15

Changes since langchain-anthropic==0.1.13

anthropic[patch]: Release 0.1.15, fix sdk tools break (#22369)
anthropic: release 0.1.14rc2, test release note gen (#22147)
anthropic[patch]: allow tool call mutation (#22130)
docs: fix some spelling mistakes caught by newest version of code spell (#22090)
anthropic, openai: cut pre-releases (#22083)
core, partners: add token usage attribute to AIMessage (#21944)
infra: rm unused # noqa violations (#22049)
Revert "anthropic: set default model" (#21987)
anthropic: set default model (#21986)
partners: bump core in packages implementing ls_params (#21868)
core, standard tests, partner packages: add test for model params (#21677)