Add or remove keys from an action's execution info based on action
mnemonic. Applies only to actions which support execution info. Many
common actions support execution info, e.g. Genrule, CppCompile, Javac,
StarlarkAction, TestRunner. When specifying multiple values, order matters
because many regexes may apply to the same mnemonic.
Syntax: "regex=[+-]key,regex=[+-]key,...".
Examples:
'.*=+x,.*=-y,.*=+z' adds 'x' and 'z' to, and removes 'y' from, the
execution info for all actions.
'Genrule=+requires-x' adds 'requires-x' to the execution info for all
Genrule actions.
'(?!Genrule).*=-requires-x' removes 'requires-x' from the execution info
for all non-Genrule actions.