gh-124889: Remove redundant artificial rules in PEG parser (#124893)

Cache in C PEG-generator reworked:
we save artificial rules in cache by Node string representation as a key instead of Node object itself.
As a result total count of artificial rules in parsers.c is lowered from 283 to 170.
More natural number ordering is used for the names of artificial rules.

Auxiliary method CCallMakerVisitor._generate_artificial_rule_call is added.
Its purpose is abstracting work with artificial rules cache.

Explicit using of "is_repeat1" kwarg is added to visit_Repeat0 and visit_Repeat1 methods.
Its slightly improve code readabitily.