Bar graphs should only get latest historical datum

[shefalijoshi]

Closes #7781

Describe your changes:

Since bar graphs only need the latest telemetry, set the size of historical request to 1

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 58.68%. Comparing base (21a4335) to head (b440bf2).
Report is 3 commits behind head on master.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #7811      +/-   ##
==========================================
+ Coverage   56.14%   58.68%   +2.54%     
==========================================
  Files         674      674              
  Lines       27283    27283              
  Branches     2669     2669              
==========================================
+ Hits        15317    16012     +695     
+ Misses      11629    11223     -406     
+ Partials      337       48     -289     

Flag	Coverage Δ
e2e-ci	61.03% <ø> (+5.54%)	⬆️
e2e-full	23.52% <ø> (-31.61%)	⬇️
unit	51.19% <ø> (+1.64%)	⬆️

Files with missing lines	Coverage Δ
src/plugins/charts/bar/BarGraphView.vue	67.64% <ø> (+7.05%)	⬆️

... and 159 files with indirect coverage changes

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[ozyx]

Just a couple minor comments and a question

[ozyx]

Running the e2e test 10x in a docker env that matches our CI environment demonstrates inherent flakiness due to the lack of determinate waits:

I think we should move this test to the openmct-yamcs side so we can test it against real network requests in addition to having deterministic wait conditions via waitForRequest()

[unlikelyzero]

Now that we have tests in the openmct-yamcs PR, let's remove the tests from this PR