Add cache_pygates feature to accelerate crate.

[raynelfss]

Summary

The following commits add the cache_pygates feature from the circuit crate into accelerate.

Details and comments

Since we added rust native methods to add operations into the DAGCircuit (thanks in part to #13143), we make use of the cache_pygate feature which is only available in the circuit crate. A couple of transpiler passes which require building instances of DAGCircuit from Rust entirely (mainly #13141, and #13137) are using these functions, they need to respect the bounds this feature specifies or else they would not compile.

A couple of teammates have already implemented this flag as part of their PRs but, to prevent a future merge conflict debacle, I decided to put it in this PR. These commits add the feature to accelerate so that people don't have to worry about that in the future.

[qiskit-bot]

One or more of the following people are relevant to this code:

• @Qiskit/terra-core

[mtreinish]

LGTM this is a straightforward addition and one I've done in some local code that isn't quite ready for a PR so glad to spin it out here even if nothing is using it yet.

[coveralls]

Pull Request Test Coverage Report for Build 10927852001

Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 13 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.008%) to 88.819%

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Files with Coverage Reduction	New Missed Lines	%
crates/qasm2/src/parse.rs	6	97.61%
crates/qasm2/src/lex.rs	7	92.48%

Totals
Change from base Build 10926067236:	-0.008%
Covered Lines:	73475
Relevant Lines:	82724

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💛 - Coveralls