Merge bitcoin#22138: script: fix spelling linter raising spuriously on "invokable"

8050eb4 script: fix spelling linter raising spuriously on "invokable" (Jon Atack)

Pull request description:

  "invokable" is a valid word that means to be callable, but the linter is raising on it:
  ```
  $ test/lint/lint-spelling.sh
  contrib/guix/guix-attest:18: invokable ==> invocable
  contrib/guix/guix-clean:18: invokable ==> invocable
  contrib/guix/guix-verify:18: invokable ==> invocable
  ^ Warning: codespell identified likely spelling errors. Any false positives? Add them to the list of ignored words in test/lint/lint-spelling.ignore-words.txt
  ```

ACKs for top commit:
  MarcoFalke:
    cr ACK 8050eb4

Tree-SHA512: 43f8dc7b7adb00ae563ccfe04a64a7ceb50237f24ff87209062bf57b2564b4d38a409df80e0183aa4f40ab306b5e07d7a5fad1600d41705bd3c443ed66a6d1c1

Author: MarcoFalke

test/lint/lint-spelling.ignore-words.txt

@@ -9,6 +9,7 @@ fpr
 hights
 hist
 inout
+invokable
 mor
 nin
 ser