PR #17568: Fix spelling error in Initializer warning

Imported from GitHub PR #17568

This PR fixes a minor spelling error `initializer` -> `initializer` in the warning message. Spelling errors could possibly block CI pipelines e.g., if it has a spell check set up to check even warning messages that come from notebooks. We've run into this in https://github.com/NVIDIA-Merlin/models when we ran `codespell` on our notebooks which usually include all outputs.
Copybara import of the project:

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5688b5a by edknv <edwardk@nvidia.com>:

Fix spelling error in Initializer warning

Merging this change closes #17568

FUTURE_COPYBARA_INTEGRATE_REVIEW=#17568 from edknv:fix_spelling_initalizer 5688b5a
PiperOrigin-RevId: 509938515

keras/initializers/initializers.py

@@ -122,7 +122,7 @@ def _warn_reuse(self):
                     "and being called multiple times, which will return "
                     "identical values each time (even if the initializer is "
                     "unseeded). Please update your code to provide a seed to "
-                    "the initializer, or avoid using the same initalizer "
+                    "the initializer, or avoid using the same initializer "
                     "instance more than once."
                 )
         else: