Remove uses of t() in assert[No]FieldBy*() calls

Reroll # 2 as patch failed to apply

Hi, I have tested the issue and the patch applies cleanly. Attaching the test result.

$ vendor/bin/phpunit -c core/ --filter ExposedFormTest
PHPUnit 8.5.5 by Sebastian Bergmann and contributors.

Testing
.........                                                           9 / 9 (100%)

Time: 4.58 minutes, Memory: 833.00 MB

OK (9 tests, 137 assertions)

$ vendor/bin/phpunit -c core/ --filter DefaultViewsTest
PHPUnit 8.5.5 by Sebastian Bergmann and contributors.

Testing
.....                                                               5 / 5 (100%)

Time: 2.75 minutes, Memory: 833.00 MB

OK (5 tests, 228 assertions)

$ vendor/bin/phpunit -c core/ --filter ExposedFormUITest                                                                                                                                            130 ↵
PHPUnit 8.5.5 by Sebastian Bergmann and contributors.

Testing
....                                                                4 / 4 (100%)

Time: 2.65 minutes, Memory: 833.00 MB

OK (4 tests, 252 assertions)

Failing test passes in local. Looks like a random javascript test failure. Queuing for test again.

#4 does not seem to have anything in common with #2.

Also it would be good to temporarily add a conditional deprecation so that when a t() object is passed in, a deprecation error is thrown. This would give us confidence that there are no more cases left out. When confirmed, then, we can remove the temporary deprecation from the patch before RTBC.

Removed uses of t() from assertFieldByName(), assertFieldByXpath() and assertNoFieldByXPath() functions.

Added the suggested test deprecation, found several missing cases, increased scope to all assert[No]FieldBy* methods (as they all eventually call the XPath methods, and that is where the test deprecation lives)

Forgot the interdiff

Working on this.

Here I have tried to fix the failed test of patch #11.

Replaced deprecated AssertLegacyTrait::assertFieldByXPath() and AssertLegacyTrait::assertNoFieldByXPath() functions.

#18 doesn't apply.

#21 doesn't apply.

@Megha_kundar please upload interdiffs when working on patches, and comment to say what you have changed, as it helps reviewers figure out what has been done.

I am not sure about the scope here - most of the assert[No]FieldBy*() calls have been converted to WebAssert already, and converrsion of assert[No]FieldByXPath() is ready for review at #3139429: Replace usages of AssertLegacyTrait::assert(No)FieldByXPath, that is deprecated - if that goes in first this issue will have no more material.

How about postponing on that, and then rescope this issue to fix assertSession()->fieldValue[Not]Equals instead?

Closing as duplicate, there are no instances remaining if I grep for assert(No)?FieldBy.*t\(