tidy-up: miscellaneous

- drop more uses of the word "just". (not enforced here)
- drop some uses of the "will" word.
- "then" -> "than".
- tests/http/testenv/curl.py: fix copy-paste typo in error message.
- pytest: replace `shutdownh` with `shutdown` in test names.
  Spotted by GitHub Code Quality.
- comment typos.
- whitespace and newlines fixes.

Closes #21830

.github/stale.yml

@@ -15,7 +15,7 @@ staleLabel: stale
 # Comment to post when marking an issue as stale. Set to `false` to disable
 markComment: >
   This issue has been automatically marked as stale because it has not had
-  recent activity. It will be closed if no further activity occurs. Thank you
+  recent activity. It is closed if no further activity occurs. Thank you
   for your contributions.
 # Comment to post when closing a stale issue. Set to `false` to disable
 closeComment: false

.github/workflows/macos.yml

@@ -658,7 +658,7 @@ jobs:
           # Reduce build combinations, by dropping less interesting ones
           - { image: macos-26, compiler: 'gcc-13' }
           - { compiler: 'gcc-14' , build: cmake }
-          # Reduce autotools to just one job that is also build with cmake
+          # Reduce autotools to only one job that is also build with cmake
           - { compiler: 'gcc-13' , build: autotools }
           - { compiler: 'gcc-14' , build: autotools }
           - { compiler: 'gcc-15' , build: autotools }