Nextion draw QR code at runtime

[edwardtfn]

What does this implement/fix?

This adds the qrcode method to Nextion library, allowing to plot QR codes on any Nextion page without the need of a QR code component previously added to the TFT.
This isn't the exactly same qr_code from display component as Nextion already have it's own QR code generator and it didn't requires a QR code component at build time.

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other

Related issue or feature (if applicable): N/A

Pull request in esphome-docs with documentation (if applicable): N/A - Nextion docs don't includes this kind of method documentation, so I've added inline doc only, keeping consistency with existing methods.

Test Environment

• ESP32
• ESP32 IDF
• ESP8266
• RP2040
• BK72xx
• RTL87xx

Example entry for config.yaml:

# Example config.yaml
display:
  - id: disp1
    platform: nextion

text:
  - id: nextion_qrcode
    name: QR code
    platform: template
    icon: mdi:qrcode-scan
    restore_value: false
    initial_value: ""
    mode: text
    set_action:
      then:
        - lambda: |-
            static const char *const TAG = "text.nextion_qrcode.set_action";
            ESP_LOGD(TAG, "Plotting new QR code: %s", x.c_str());
            disp1->qrcode(113, 62, x.c_str(), 222, 65535, 0, -1, 7);

Checklist:

• The code change is tested and works locally.
• Tests have been added to verify that the new code works (under tests/ folder).

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated in esphome-docs.

[probot-esphome]

Hey there @SenexCrenshaw, mind taking a look at this pull request as it has been labeled with an integration (nextion) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}