dtl: Support Basic Authentication for RPC endpoints

[Inphi]

Description
Adds optional support for Basic Authentication for RPC endpoints.

Note: This is technically a breaking change because prior to this patch we inadvertently support multiple RPC endpoints as a csv, via the FallbackProvider. Now only a single endpoint will work.

Metadata
ENG-2062

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🦋 Changeset detected

Latest commit: 2163f1a

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@eth-optimism/data-transport-layer	Patch

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[codecov-commenter]

Codecov Report

Merging #2322 (096f213) into develop (ccd9881) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff            @@
##           develop    #2322   +/-   ##
========================================
  Coverage    80.08%   80.08%           
========================================
  Files           77       77           
  Lines         2460     2460           
  Branches       450      450           
========================================
  Hits          1970     1970           
  Misses         490      490           

Flag	Coverage Δ
contracts	99.29% <ø> (ø)
core-utils	86.77% <ø> (ø)
data-transport-layer	49.72% <ø> (ø)
sdk	55.75% <ø> (ø)

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[tynes]

We previously only did minor releases when we did a regenesis. I'm not super opinionated on whether or not we should continue not following semver the way that it was supposed to be used

[tynes]

proxyd should be able to handle the retry logic now, so making this change should be fine

[mslipper]

What's the context for adding auth? Is there an upstream provider that requires this?

[Inphi]

We previously only did minor releases when we did a regenesis. I'm not super opinionated on whether or not we should continue not following semver the way that it was supposed to be used

I see. I can make it patch in that case. We should have a discussion later about this though.

[tynes]

proxyd supports auth, so this would allow the dtl to consume proxyd that is set up with auth