Update spec/2023-07-draft.md

Co-authored-by: Fredrik Niemelä <[email protected]>

spec/2023-07-draft.md

@@ -97,7 +97,7 @@ If at least one of these two files is included:
    The working directory will be (a copy of) the program directory.
    The `run` file must exist in that directory and be executable after `build` is done.
 2. Then, the `run` file (which now exists, and is an executable binary or POSIX-compliant shell script)
-   will be used as the validator or visualizer program.   
+   will be used as the validator or visualizer program.
 
 Scripts may assume that a C and C++ compiler are available on the system search path, aliased to `cc` and `cpp` respectively.