gh-41132: Check sagemath kernel integrity robustly
    
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Fix a bug discussed in https://groups.google.com/g/sage-
devel/c/rxfhmspCeuw

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### ⌛ Dependencies

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URL: #41132
Reported by: Kwankyu Lee
Reviewer(s):

Author: Release Manager

src/sage/repl/ipython_kernel/install.py

@@ -257,15 +257,23 @@ def check(cls):
         try:
             spec = get_kernel_spec(ident)
         except NoSuchKernel:
-            warnings.warn(f'no kernel named {ident} is accessible; '
+            warnings.warn(f'No kernel named {ident} is accessible; '
                           'check your Jupyter configuration '
-                          '(see https://docs.jupyter.org/en/latest/use/jupyter-directories.html)')
+                          '(see https://docs.jupyter.org/en/latest/use/jupyter-directories.html).')
         else:
+            import sys
+            import shutil
             from pathlib import Path
-            if Path(spec.argv[0]).resolve() != Path(os.path.join(SAGE_VENV, 'bin', 'sage')).resolve():
-                warnings.warn(f'the kernel named {ident} does not seem to correspond to this '
+            kernel_executable = shutil.which(spec.argv[0])
+            if not kernel_executable:
+                warnings.warn(f'The kernel named {ident} does not seem to be runnable; '
+                              'check your Jupyter configuration '
+                              '(see https://docs.jupyter.org/en/latest/use/jupyter-directories.html).')
+                return
+            if Path(kernel_executable).resolve() != Path(sys.executable).resolve():
+                warnings.warn(f'The kernel named {ident} does not seem to correspond to this '
                               'installation of SageMath; check your Jupyter configuration '
-                              '(see https://docs.jupyter.org/en/latest/use/jupyter-directories.html)')
+                              '(see https://docs.jupyter.org/en/latest/use/jupyter-directories.html).')
 
 
 def have_prerequisites(debug=True) -> bool: