feat(expect): updates test suite to use expectation api

tests/.snapshots/success.txt

@@ -110,31 +110,16 @@
    PASS  Tests\Expect\toBeString
   ✓ pass
   ✓ failures
+  ✓ not failures
+
+   PASS  Tests\Expect\toBeTrue
+  ✓ strict comparisons
+  ✓ failures
   ✓ not failures
 
    PASS  Tests\Expect\toContain
   ✓ passes
   ✓ failures
-  ✓ not failures
-
-   PASS  Tests\Expect\toContainOnly
-  ✓ pass
-  ✓ failures
-  ✓ not failures
-
-   PASS  Tests\Expect\toContainOnlyInstancesOf
-  ✓ pass
-  ✓ failures
-  ✓ not failures
-
-   PASS  Tests\Expect\toContainString
-  ✓ is case sensitive
-  ✓ failures
-  ✓ not failures
-
-   PASS  Tests\Expect\toContainStringIgnoringCase
-  ✓ ignore difference in casing
-  ✓ failures
   ✓ not failures
 
    PASS  Tests\Expect\toCount
@@ -231,9 +216,9 @@
    PASS  Tests\Features\HigherOrderTests
   ✓ it proxies calls to object
 
-   PASS  Tests\Features\It
+   WARN  Tests\Features\It
   ✓ it is a test
-  ✓ it is a higher order message test
+  ! it is a higher order message test → This test did not perform any assertions  /Users/nunomaduro/pestphp/pest/src/Factories/TestCaseFactory.php(204) : eval()'d code:4
 
    PASS  Tests\Features\Macro
   ✓ it can call chained macro method
@@ -243,8 +228,8 @@
   ✓ it has bar
 
    PASS  Tests\Features\PendingHigherOrderTests
-  ✓ get 'foo' → get 'bar' → assertTrue true
-  ✓ get 'foo' → assertTrue true
+  ✓ get 'foo' → get 'bar'
+  ✓ get 'foo'
 
    WARN  Tests\Features\Skip
   ✓ it do not skips
@@ -255,9 +240,9 @@
   ✓ it do not skips with falsy closure condition
   - it skips with condition and message → skipped because foo
 
-   PASS  Tests\Features\Test
+   WARN  Tests\Features\Test
   ✓ a test
-  ✓ higher order message test
+  ! higher order message test → This test did not perform any assertions  /Users/nunomaduro/pestphp/pest/src/Factories/TestCaseFactory.php(204) : eval()'d code:4
 
    PASS  Tests\Fixtures\DirectoryWithTests\ExampleTest
   ✓ it example 1
@@ -327,5 +312,5 @@
    WARN  Tests\Visual\Success
   - visual snapshot of test suite on success
 
-  Tests:  6 skipped, 192 passed
-  Time:   5.20s
+  Tests:  2 risked, 6 skipped, 181 passed
+  Time:   5.72s