Fix link to CLA (conan-io#19007)

Author: Chris Mc

CONTRIBUTING.md

@@ -23,7 +23,7 @@ To contribute follow the next steps:
 
 1. Comment in the corresponding issue that you want to contribute the package/fix proposed. If there is no open issue, we strongly suggest
    opening one to gather feedback.
-2. Make sure to [request access](docs/adding_packages/README.md#request-access) and be aware there is a [CLA](docs/CONTRIBUTOR_LICENSE_AGREEMENT.md).
+2. Make sure to [request access](docs/adding_packages/README.md#request-access) and be aware there is a [contributor licenses agreement](https://cla-assistant.io/conan-io/conan-center-index).
 3. Get setup by following the [Developing Recipes](docs/developing_recipes_locally.md) guide and learn the basic commands.
 4. Check the [How To Add Packages](docs/adding_packages/README.md) page for the break down of ConanCenterIndex specific conventions and practices.
 5. In your fork create a `package/xxx` branch from the `master` branch and develop

docs/CONTRIBUTOR_LICENSE_AGREEMENT.md

@@ -30,7 +30,7 @@ generally approved on a weekly basis. Feel free to continue to step :two: while
 > All interactions are subject to the expectations of the [code of conduct](../code_of_conduct.md). Any misuse or inappropriate behavior
 > are subject to the same principals.
 
-When submitting a pull request for the first time, you will be prompted to sign the [CLA](../CONTRIBUTOR_LICENSE_AGREEMENT.md) for your
+When submitting a pull request for the first time, you will be prompted to sign the [CLA](https://cla-assistant.io/conan-io/conan-center-index) for your
 code contributions. You can view your signed CLA's by going to <https://cla-assistant.io/> and signing in.
 
 ## Inactivity and user removal

docs/adding_packages/README.md

@@ -101,7 +101,7 @@ The bot runs Automatic Merges every 20 minutes. Currently, it can only merge a s
 PR is selected for the merge only if:
 
 - Author is already [approved](https://github.com/conan-io/conan-center-index/issues/4).
-- Author has signed the [CLA](CONTRIBUTOR_LICENSE_AGREEMENT.md).
+- Author has signed the [CLA](https://cla-assistant.io/conan-io/conan-center-index).
 - PR is not a Draft.
 - PR has a green status (successful build).
 - PR doesn't have merge conflicts with `master` branch.