增加圖片上傳中的狀態提示

[Yukaii]

Describe the bug
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請清晰詳細的描述這個問題

To Reproduce
Steps to reproduce the behavior:
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1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expected behavior
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Screenshots
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截圖

Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context

Add any other context about the problem here.

[Yukaii]

補充上傳圖片時的按鈕，應在圖片上傳時，顯示為「上傳中......」

[Yukaii]

frontend/src/components/UpdateFactorySteps.vue

Lines 62 to 74 in 5a70e15

	<image-upload-form
	v-if="appState.isEditImagesMode"
	v-model="selectedImages"
	:uploading="imageUploadState.uploading"
	:error="imageUploadState.error"
	:previewImages="uploadedImages"
	:onClickRemoveImage="onClickRemoveImage"
	:valid="imagesValid"
	:submit="submitImageUpload"
	:formState="imageUploadFormState"
	submitText="確認新增照片"
	disableProgressiveUpload
	/>

參考 vue template uploading 的判斷，顯示上傳中或 submitText

frontend/src/components/ImageUploadForm.vue

Lines 59 to 63 in d609f9e

	<div class="bottom-button-container w-100 d-flex justify-center align-items-center px-xs-3 pb-md-9">
	<v-btn x-large rounded @click="onSubmit" :disabled="!valid" style="width: 100%; max-width: 345px;" color="primary">
	{{ submitText || '下一步' }}
	</v-btn>
	</div>