[simplebar-vue] fix: move vue-demi to dependencies

[renatodeleao]

First I would like to apologise for breaking the 1.7.0 build :/
I've trusted unit testing and forgot to install it externally to ensure it works in real life, or should have asked you to release it as beta.

simplebar/packages/simplebar-vue/utils.js

Lines 1 to 6 in 3c5cb8d

	import { isVue3 } from 'vue-demi';
	export const lifecycleEventNames = {
	beforeUnmount: isVue3 ? 'beforeUnmount' : 'beforeDestroy',
	unmount: isVue3 ? 'unmount' : 'destroy'
	};

1. vue-demi is not only used for testing but also to dynamically create the lifecyle names map for cross-compatiblity with vue 2 and 3
2. updated vue-demi to latest version, I was going crazy to make the tests work and thought that vue-demi had something to do with it but I has not.

[Grsmto]

I see. That's my bad I tested that badly I think. I'm merging this now and giving it a test (I'm adding a new example in the /examples folder specifically for vue 3). If that works I'll release a patch.

[Grsmto]

@renatodeleao I just published a patch, if you can give it a try!

[renatodeleao]

@Grsmto tried, from my tests it works on vue3 but not on vue2 even prefixing the build script with npm run use-vue:2.7 does not change the outcome (not sure why).

It seems that I underestimated the task: my past experience with cross-compatible components I used solely render functions and didn't involve compiling SFC (.vue) and that's apparently where the problem is: the compiled output of SFC is a render function tailored for vue3 that does not work in vue2. There's scattered information around the web on how to do it right and these issues on vue-demi have listed the most workarounds but none is considered a de facto solution.

• Vue3 lib not working in Vue2 projects vueuse/vue-demi#152
• docs: added remark about component libraries vueuse/vue-demi#154
• it's hard for developer to write a common component with vue-demi  vueuse/vue-demi#153

Since I've promised vue2 and vue3 support and now have to deliver, what I can do in the short-term to mitigate the failed release is basically re-writing the <template> as a plain render function with some conditionals for handling the differences between vue 2 and 3 signatures. I already managed to make it work for vue2.7 and vue3 renatodeleao@33146ca , but I'm not sure If I'm going to make it for vue 2.6 which if becomes true tomorrow, means a breaking change version.

Once again, sry for the trouble, I had the best intentions when I suggested this feature didn't expect so many issues down the road!

[Grsmto]

@renatodeleao indeed I have tested only the vue 3 version but the vue 2 is not working. I will revert to the previous vue 2 support for now to avoid too many side effects from people upgrading to latest version.

[renatodeleao]

@Grsmto You did well in reverting, thanks and sry!
The good news is that I have a — hopefully 🤞 — working version that is fully cross-compatible. Will push it sometime today!

[Grsmto]

Great stuff. Let's not do the same mistake and do a pre-release to test it this time! 😅