get ecr pairs from coupling map

[nbronn]

Added method finding coupling map where only cx defined by echoed cross resonance pulses are returned. This is currently necessary because pulse scaling is not defined for Direct CX pulses.

[coveralls]

Pull Request Test Coverage Report for Build 4774608379

• 1 of 9 (11.11%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.2%) to 85.42%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
qiskit_research/utils/pulse_scaling.py	1	9	11.11%

Totals
Change from base Build 4774588418:	-0.2%
Covered Lines:	2320
Relevant Lines:	2716

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💛 - Coveralls

[kevinsung]

The changes to getting_started.ipynb are unrelated right?

[nbronn]

The changes to getting_started.ipynb are unrelated right?

That's right... anything changes to that file were me running cells while still in this working branch.