feat(stepper): explicit disabling of stepper controls

[adisreyaj]

Adds support for explicitly disabling stepper control buttons:

• Back
• Cancel
• Next
• Submit

Use-case: One common use case, is to disable the Submit button when data is getting saved.

[github-actions[bot]]

Unit Test Results

       4 files  ±0     297 suites  ±0   22m 56s :stopwatch: + 1m 40s 1 072 tests +4  1 072 :heavy_check_mark: +4  0 :zzz: ±0  0 :x: ±0  1 080 runs  +4  1 080 :heavy_check_mark: +4  0 :zzz: ±0  0 :x: ±0 

Results for commit 1da0c553. ± Comparison against base commit d26841d8.

[codecov[bot]]

Codecov Report

Merging #1870 (1da0c55) into main (d26841d) will increase coverage by 0.01%. The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #1870      +/-   ##
==========================================
+ Coverage   83.36%   83.37%   +0.01%     
==========================================
  Files         886      886              
  Lines       19375    19387      +12     
  Branches     2731     2734       +3     
==========================================
+ Hits        16151    16163      +12     
  Misses       3084     3084              
  Partials      140      140              

Impacted Files	Coverage Δ
...ojects/components/src/stepper/stepper.component.ts	87.14% <100.00%> (+2.66%)	:arrow_up:

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[23nobody]

Why do we want to be disabling back and cancel?

[arjunlalb]

it’ll be better if we can bake this config onto the stepper tab component as individual controls so that change detection can be leveraged

[adisreyaj]

Why do we want to be disabling back and cancel?

Future proofing.