Add acceptance test flags in makefile for autocompletion

[skshetry]

Description

This PR adds flag to the makefile, so that, if your terminal support this (zsh, maybe fish as well), you'll get autocompletion for makefile env variables. Sadly, bash-completions does not support variable autocompletion.

Related Issue

Motivation and Context

Just felt like it would help.

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Database schema changes (next release will require increase of minor version instead of patch)
• Breaking change (fix or feature that would cause existing functionality to change)
• Technical debt
• Tests only (no source changes)

Checklist:

• Code changes
• Unit tests added
• Acceptance tests added
• Documentation ticket raised:

Open tasks:

• Backport (if applicable set "backport-request" label and remove when the backport was done)

[codecov]

Codecov Report

Merging #35271 into master will increase coverage by 0.86%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master   #35271      +/-   ##
============================================
+ Coverage     65.53%   66.39%   +0.86%     
+ Complexity    18648    18647       -1     
============================================
  Files          1218     1157      -61     
  Lines         70549    63234    -7315     
  Branches       1288        0    -1288     
============================================
- Hits          46236    41987    -4249     
+ Misses        23936    21247    -2689     
+ Partials        377        0     -377

Flag	Coverage Δ	Complexity Δ
#javascript	?	?
#phpunit	66.39% <ø> (-0.51%)	18647 <ø> (-1)

Impacted Files	Coverage Δ	Complexity Δ
lib/private/DB/MySQLMigrator.php	0% <0%> (-100%)	5% <0%> (ø)
lib/private/Repair/Collation.php	0% <0%> (-87.5%)	12% <0%> (ø)
...ivate/Files/ObjectStore/HomeObjectStoreStorage.php	0% <0%> (-86.67%)	8% <0%> (ø)
lib/private/Repair/InnoDB.php	0% <0%> (-78.95%)	6% <0%> (ø)
...ilder/ExpressionBuilder/MySqlExpressionBuilder.php	0% <0%> (-62.5%)	3% <0%> (ø)
lib/private/DB/AdapterMySQL.php	0% <0%> (-50%)	4% <0%> (ø)
lib/private/Files/Storage/Wrapper/Availability.php	10.38% <0%> (-38.97%)	80% <0%> (ø)
lib/private/Files/ObjectStore/NoopScanner.php	68.75% <0%> (-18.75%)	6% <0%> (ø)
lib/private/Share/Share.php	27.04% <0%> (-16.33%)	70% <0%> (ø)
lib/private/DB/ConnectionFactory.php	75.36% <0%> (-14.5%)	20% <0%> (ø)
... and 84 more

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #35271 into master will not change coverage.
The diff coverage is n/a.

@@            Coverage Diff            @@
##             master   #35271   +/-   ##
=========================================
  Coverage     65.53%   65.53%           
  Complexity    18648    18648           
=========================================
  Files          1218     1218           
  Lines         70549    70549           
  Branches       1288     1288           
=========================================
  Hits          46236    46236           
  Misses        23936    23936           
  Partials        377      377

Flag	Coverage Δ	Complexity Δ
#javascript	53.69% <ø> (ø)	0 <ø> (ø)	⬇️
#phpunit	66.89% <ø> (ø)	18648 <ø> (ø)	⬇️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8fac319...44edc6b. Read the comment docs.

[phil-davis]

Please mention the shells that you know will work for this.
It will help other people to understand if they have any hope to use it.

[skshetry]

@phil-davis, this currently only supports zsh (maybe, fish), but not the bash. So, if you think it would not help many, we could close this. Or else, we could merge this. 😀

[phil-davis]

Works for me with zsh. It will be useful for anyone that happens to use a shell with this support.

[phil-davis]

It broke CI. Maybe it sees BEHAT_FEATURE as an empty string?
And so nothing runs.

Forgot about the exports. It should now work

[skshetry]

Backport for stable10 on #35383