Alt text is not descriptive [/src/**/start files]

**Describe the content issue**:
Images listed below do not have descriptive/informative alt text. For markdown the alt text is located between the square brackets, ``.

The list below isn't exhaustive since I found these images based on the word count for the alt text, but it should be a good starting point to make our alt text better for people who use screen readers.

Some resources to help write alt text:
- https://webaim.org/techniques/alttext/
- https://www.a11yproject.com/posts/are-you-making-these-five-mistakes-when-writing-alt-text/

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/angular/hosting.mdx:
```
43
44: 
45
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/flutter/integrate.mdx:
```
212
213: 
214

290
291: 
292

493
494: 
495

573
574: 
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/ios/setup.mdx:
```
53
54: 
55

59
60: 
61

63
64: 
65

73
74: 
75
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/next/hosting.mdx:
```
24
25: 
26

28
29: 
30

34
35: 
36
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/reactnative/generate-model.mdx:
```
12
13: 
14

23
24: 
25
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/vanillajs/hosting.mdx:
```
29
30: 
31
```

 

https://github.com/aws-amplify/docs/blob/main/src/pages/[platform]/start/getting-started/hosting/index.mdx:
```
101
102: 
103

107
108: 
109
```

 

https://github.com/aws-amplify/docs/blob/main/src/pages/[platform]/start/getting-started/hosting/index.mdx:
```
101
102: 
103

107
108: 
109
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/ios/add-api.mdx:
```
141
142: 
143

168
169: 
170
```

 

https://github.com/aws-amplify/docs/blob/main/src/fragments/start/getting-started/ios/setup.mdx:
```
22
23: 2. Select **iOS** tab, choose Application type as **App**, and then click on **Next**. 
24

31
32: 
33
```