[BUG] SoloPi 第一次启动加载插件时可能失败

**Describe the bug / 问题描述**
SoloPi 第一次启动加载时可能失败，报错如下：

插件加载失败，原因:Failed to connect to raw.githubusercontent/com/151.101.228.133:443

**To Reproduce / 复现流程**
1. 卸载 SoloPi app
2. 重新安装：`adb install SoloPi.apk`
3. 启动 SoloPi，偶现上述报错

**Error Stack/错误堆栈**
完整日志文件：
[solopi.log](https://github.com/alipay/SoloPi/files/4059126/solopi.log)

截取了其中一行报错日志如下：

1578995385552,2020.01.14 17:49:45.552,
ERROR,
SoloPi-AssetsManager,
Download failed: Connection failed with
request[
{
accept=[*/*],
if-match=[W/"828c012d338187b10d6f92809d40ffd3fdebb177cb5a46c35693e8af69e2d15e"],
range=[bytes=0-],
user-agent=[FileDownloader/1.7.7]
}
]
response[
{
accept-ranges=[bytes, bytes],
access-control-allow-origin=[*],
connection=[keep-alive],
content-length=[452],
content-type=[text/html; charset=utf-8],
date=[Tue, 14 Jan 2020 09:49:45 GMT],
expires=[Tue, 14 Jan 2020 09:54:45 GMT],
retry-after=[0],
server=[Varnish],
vary=[Authorization,Accept-Encoding],
via=[1.1 varnish],
x-cache=[MISS],
x-cache-hits=[0],
x-fastly-request-id=[b72b6f6265d5358887efd94c243f5fc3ba967f3b],
x-served-by=[cache-tyo19943-TYO],
x-timer=[S1578995385.113235,VS0,VE1]
}
] http-state[412] on task[-1262172314--1],
which is changed after verify connection, so please try again. :

java.net.SocketException: Connection failed with
request[{accept=[*/*], if-match=[W/"828c012d338187b10d6f92809d40ffd3fdebb177cb5a46c35693e8af69e2d15e"], range=[bytes=0-], user-agent=[FileDownloader/1.7.7]}]
response[{accept-ranges=[bytes, bytes], access-control-allow-origin=[*], connection=[keep-alive], content-length=[452], content-type=[text/html; charset=utf-8], date=[Tue, 14 Jan 2020 09:49:45 GMT], expires=[Tue, 14 Jan 2020 09:54:45 GMT], retry-after=[0], server=[Varnish], vary=[Authorization,Accept-Encoding], via=[1.1 varnish], x-cache=[MISS], x-cache-hits=[0], x-fastly-request-id=[b72b6f6265d5358887efd94c243f5fc3ba967f3b], x-served-by=[cache-tyo19943-TYO], x-timer=[S1578995385.113235,VS0,VE1]}]

http-state[412] on task[-1262172314--1], which is changed after verify connection, so please try again.

at com.liulishuo.filedownloader.b.e.run(SourceFile:97)

at com.liulishuo.filedownloader.b.d.c(SourceFile:609)

at com.liulishuo.filedownloader.b.d.run(SourceFile:295)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)

at java.lang.Thread.run(Thread.java:764)

**Screenshots / 截图**

**Device Info / 设备信息**

"厂家":"oppo"
"设备":"R17"
"系统版本":"Android 8.1.0"
"SoloPi版本":"0.10.1"
"cpu":{
"Processor : AArch64 Processor rev 12 (aarch64)",
"processor : 0",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x7",
"CPU part : 0x803",
"CPU revision : 12",

"processor : 1",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x7",
"CPU part : 0x803",
"CPU revision : 12",

"processor : 2",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x7",
"CPU part : 0x803",
"CPU revision : 12",

"processor : 3",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x7",
"CPU part : 0x803",
"CPU revision : 12",

"processor : 4",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x7",
"CPU part : 0x803",
"CPU revision : 12",

"processor : 5",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x7",
"CPU part : 0x803",
"CPU revision : 12",

"processor : 6",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x6",
"CPU part : 0x802",
"CPU revision : 13",

"processor : 7",
"BogoMIPS : 38.40",
"Features : fp asimd evtstrm aes pmull sha1 sha2 crc32 atomics fphp asimdhp",
"CPU implementer : 0x51",
"CPU architecture: 8",
"CPU variant : 0x6",
"CPU part : 0x802",
"CPU revision : 13",

"Hardware : Qualcomm Technologies, Inc SDM670",
}

**Additional context/其他内容**
失败概率蛮高的，处于相同的办公网络环境下也会偶发失败，今天的实验7次失败4次