docs(autocomplete, input, input-text): update pattern context for res…

…iding in a parent form (#11285)

**Related Issue:** #11148

## Summary
Updates the `pattern` prop in `autocomplete`, `input`, and `input-text`
that to use the prop the component must reside within a form element,
re:
#11148 (comment).

packages/calcite-components/src/components/autocomplete/autocomplete.tsx

@@ -241,7 +241,8 @@ export class Autocomplete
   @property({ reflect: true }) overlayPositioning: OverlayPositioning = "absolute";
 
   /**
-   * Specifies a regex pattern the component's `value` must match for validation.
+   * When the component resides in a form,
+   * specifies a regular expression (regex) pattern the component's `value` must match for validation.
    * Read the native attribute's documentation on MDN for more info.
    *
    * @mdn [step](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/pattern)

packages/calcite-components/src/components/input-text/input-text.tsx

@@ -212,7 +212,8 @@ export class InputText
   @property({ reflect: true }) name: string;
 
   /**
-   * Specifies a regex pattern the component's `value` must match for validation.
+   * When the component resides in a form,
+   * specifies a regular expression (regex) pattern the component's `value` must match for validation.
    * Read the native attribute's documentation on MDN for more info.
    *
    * @mdn [step](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/pattern)

packages/calcite-components/src/components/input/input.tsx

@@ -297,7 +297,8 @@ export class Input
   @property({ reflect: true }) numberingSystem: NumberingSystem;
 
   /**
-   * Specifies a regex pattern the component's `value` must match for validation.
+   * When the component resides in a form,
+   * specifies a regular expression (regex) pattern the component's `value` must match for validation.
    * Read the native attribute's documentation on MDN for more info.
    *
    * @mdn [step](https://developer.mozilla.org/en-US/docs/Web/HTML/Attributes/pattern)