refactor(material-experimental/mdc-form-field): unset MDC custom baseline adjustment (#18892)

Recently with b2e8691, we updated to
the latest canary version of the MDC text-field. MDC updated how they
align the input vertically. We decided to still use our custom
alignment using padding that will also work for custom form field
controls.

Since we still use padding alignment, we can unset the MDC
custom baseline styles. These currently have no effect, but
will cause the form-field to always have a minimum height that
needs extra treatment for the density levels.

Author: devversion

src/material-experimental/mdc-form-field/_mdc-text-field-structure-overrides.scss

@@ -126,4 +126,14 @@
   .mat-mdc-form-field .mat-mdc-text-field-wrapper.mdc-text-field .mdc-notched-outline__notch {
     padding-top: 0;
   }
+
+  // Unset the baseline adjustment styles that are applied to the `.mdc-text-field` before
+  // pseudo element. We control the vertical alignment of form field controls using infix
+  // spacing since we support custom form-field controls. Those don't necessarily have an
+  // explicit height that matches with the Material Design specification. If the height isn't
+  // explicitly set to a specific value by MDC, the control will not align correctly vertically.
+  // e.g. No vertical spacing to the bottom-line if the control is too large.
+  .mat-mdc-text-field-wrapper::before {
+    content: none;
+  }
 }