doc: Fix typos from codespell lint

contrib/guix/README.md

@@ -295,7 +295,7 @@ rebuild _just_ this derivation in a single-threaded fashion:
 $ guix build --cores=1 /gnu/store/...-foo-3.6.12.drv
 ```
 
-If the single-threaded rebuild stil did not succeed, you may need to dig deeper.
+If the single-threaded rebuild did not succeed, you may need to dig deeper.
 You may view `foo`'s build logs in `less` like so (please replace paths with the
 path you see in the build failure output):
 

contrib/guix/guix-build

@@ -15,7 +15,7 @@ source "$(dirname "${BASH_SOURCE[0]}")/libexec/prelude.bash"
 ###################
 
 ################
-# Required non-builtin commands should be invokable
+# Required non-builtin commands should be invocable
 ################
 
 check_tools cat mkdir make git guix

contrib/guix/libexec/prelude.bash

@@ -9,7 +9,7 @@ source contrib/shell/realpath.bash
 source contrib/shell/git-utils.bash
 
 ################
-# Required non-builtin commands should be invokable
+# Required non-builtin commands should be invocable
 ################
 
 check_tools() {