Issue better errors/warnings in malformed labels

Bug description

When using v1.4.547 Quarto CLI, when the .qmd file is Previewed the HTML page contains text that is not in the Mark Down code:
::: {#cell-Q1 chart .cell execution_count=4}

Steps to reproduce

---
title: "Client Report - [Insert Project Title]"
subtitle: "Course DS 250"
author: "[STUDENT NAME]"
format:
  html:
    self-contained: true
    page-layout: full
    title-block-banner: true
    toc: true
    toc-depth: 3
    toc-location: body
    number-sections: false
    html-math-method: katex
    code-fold: true
    code-summary: "Show the code"
    code-overflow: wrap
    code-copy: hover
    code-tools:
        source: false
        toggle: true
        caption: See code
execute: 
  warning: false
    
---

_THIS `.qmd` IS INSTRUCTIONAL AND SHOULD `NOT` BE USED TO WRITE YOUR REPORT. THERE IS ANOTHER TEMPLATE FILE FOR THAT. YOU WILL NEED TO `PREVIEW` THE REPORT TO PRODUCE A `.html` FILE. YOU WILL SUBMIT THE `.html` FILE ON CANVAS._

```{python}
#| label: libraries
#| include: false
import pandas as pd
import numpy as np
import plotly.express as px
```


## Elevator pitch
_A SHORT (2-3 SENTENCES) PARAGRAPH THAT `DESCRIBES KEY INSIGHTS` TAKEN FROM METRICS IN THE PROJECT RESULTS THINK TOP OR MOST IMPORTANT RESULTS._

_A Client has requested this analysis and this is your one shot of what you would say to your boss in a 2 min elevator ride before he takes your report and hands it to the client._

```{python}
#| label: project data
#| code-summary: Read and format project data
# Include and execute your code here
df = pd.read_csv("https://github.com/byuidatascience/data4names/raw/master/data-raw/names_year/names_year.csv")
```

__Highlight the Questions and Tasks__

## Question|Task 1

__COPY PASTE QUESTION|TASK 1 FROM THE PROJECT HERE__

_Add details here to answer the question but `NOT` like an assignment Q&A. You need to `write your answers as a consulting solution report`. A Client needs to understand the answer, but also needs to understand the decisions that went into the answer (when applicable)._

_include figures in chunks and discuss your findings in the figure._

- _YOU SHOULD HAVE QUALITY WRITING THAT DESCRIBES YOUR CHARTS AND TABLES._

- _WE HIGHLY RECOMMEND [GRAMMARLY](https://grammarly.com/) TO FIX YOUR SPELLING AND GRAMMAR. WRITING TAKES TIME TO BE CLEAR. SPEND THE TIME TO PRACITCE._ 

- _YOU SHOULD HAVE QUALITY COMMENTS THAT DESCRIBES YOUR CODES. OFTEN CODEERS WORK IN TEAMS AND YOU NEED TO HAVE QUALTIY COMMENTS FOR YOUR TEAM AND YOURSELF. YOU MAY NEED TO REVISIT CODE YOU WROTE OVER A YEAR AGO, AND IF YOU DONT COMMENT IT NOW YOU WONT REMEMBER WHY YOU DID WHAT YOU DID._

```{python}
#| label: Q1
#| code-summary: Read and format data
# Include and execute your code here


```

_include figures in chunks and discuss your findings in the figure._

```{python}
#| label: Q1 chart
#| code-summary: plot example
#| fig-cap: "My useless chart"
#| fig-align: center
# Include and execute your code here

chart = px.bar(df.head(200),
    x="name", 
    y="AK"
)
chart.show()
```


- _PROVIDE TABLES THAT HELP ADDRESS THE QUESTIONS AND TASKS (IF APPLICABLE)._

```{python}
#| label: Q1 table
#| code-summary: table example
#| tbl-cap: "table example"
#| tbl-cap-location: top
# Include and execute your code here
mydat = df.head(1000)\
    .groupby('year')\
    .sum()\
    .reset_index()\
    .tail(10)\
    .filter(["year", "AK","AR"])

display(mydat)

```


Note: Non executing Python `Snippets` include (3) \`\`\` followed by (3) more \`\`\`, each on their own line. These are not single quotes, they are the key left of the number 1 key on the keyboard. The top row can include the language of code that is pasted inbetween the \`\`\`  marks. 

Note: These also work in `Slack` and it is expected they are used for any code shared in that app. No screen shots allowed.

Expected behavior

there would not be text added by the CLI process into the HTML page

Actual behavior

the CLI process is adding text from rendering the ell into the HTML page

Your environment

Win 11, VS Code (latest)

Quarto check output

No response

Temp Solution: Uninstall v1.4 and install v1.3 fixes the issue