fix(storage): resolve reST link target mismatch in README and add long_description_content_type

[codyoss]

Fixes a reST target name mismatch in README.rst and docs/README.rst that caused PyPI upload failures, and explicitly sets long_description_content_type="text/x-rst" in setup.py.

Verified with twine check (PASSED) and unit tests.

Related: #18211

[gemini-code-assist]

Code Review

This pull request corrects a typo in the README and documentation files, changing 'Setup Authentication' to 'Set up Authentication'. It also updates setup.py to include the long_description_content_type parameter set to 'text/x-rst'. No review comments were provided, and there is no additional feedback to offer.

[parthea]

We also need to update this post processing that clobbers the auto-generated README

google-cloud-python/.librarian/generator-input/client-post-processing/storage-integration.yaml

Line 287 in f0f214b

packages/google-cloud-storage/README.rst,

See the diff below after running librarian code generation

partheniou@partheniou-vm-3:~/google-cloud-python-20260826$ git diff
diff --git a/packages/google-cloud-storage/README.rst b/packages/google-cloud-storage/README.rst
index eeafe4b97ad..7422dfc8840 100644
--- a/packages/google-cloud-storage/README.rst
+++ b/packages/google-cloud-storage/README.rst
@@ -55,7 +55,7 @@ A step-by-step guide may also be found in `Get Started with Client Libraries`_.
 .. _Select or create a Cloud Platform project.: https://console.cloud.google.com/project
 .. _Enable billing for your project.: https://cloud.google.com/billing/docs/how-to/modify-project#enable_billing_for_a_project
 .. _Enable the Google Cloud Storage API.:  https://console.cloud.google.com/flows/enableapi?apiid=storage-api.googleapis.com
-.. _Set up Authentication.: https://cloud.google.com/docs/authentication/client-libraries
+.. _Setup Authentication.: https://cloud.google.com/docs/authentication/client-libraries
 
 Installation
 ~~~~~~~~~~~~
diff --git a/packages/google-cloud-storage/docs/README.rst b/packages/google-cloud-storage/docs/README.rst
index eeafe4b97ad..7422dfc8840 100644
--- a/packages/google-cloud-storage/docs/README.rst
+++ b/packages/google-cloud-storage/docs/README.rst
@@ -55,7 +55,7 @@ A step-by-step guide may also be found in `Get Started with Client Libraries`_.
 .. _Select or create a Cloud Platform project.: https://console.cloud.google.com/project
 .. _Enable billing for your project.: https://cloud.google.com/billing/docs/how-to/modify-project#enable_billing_for_a_project
 .. _Enable the Google Cloud Storage API.:  https://console.cloud.google.com/flows/enableapi?apiid=storage-api.googleapis.com
-.. _Set up Authentication.: https://cloud.google.com/docs/authentication/client-libraries
+.. _Setup Authentication.: https://cloud.google.com/docs/authentication/client-libraries
 
 Installation
 ~~~~~~~~~~~~
diff --git a/packages/google-cloud-storage/setup.py b/packages/google-cloud-storage/setup.py
index aaf15566415..036babf4a93 100644
--- a/packages/google-cloud-storage/setup.py
+++ b/packages/google-cloud-storage/setup.py
@@ -117,7 +117,6 @@ setuptools.setup(
     version=version,
     description=description,
     long_description=readme,
-    long_description_content_type="text/x-rst",
     author="Google LLC",
     author_email="googleapis-packages@google.com",
     license="Apache-2.0",