[SHIRO-887] Do not trim passwords in FormAuthenticationFilter

[sebastianfrey]

Fixes SHIRO-887.

This PR fixes an issue where passwords which start and/or end with spaces are trimmed by the FormAuthenticationFilter, which prevents login for users with such passwords.

Note: I am a first time contributor, so I have no CLA signed yet. In order to fulfill the contribution guidelines, I have sent the signed CLA to the Apache Software Foundations secretary office.

Update 2022/07/30: CLA is acknowledge.

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[sunshineandy]

这是自动回复邮件。你好，您的邮件已经发送到我的邮箱，我看过后会尽快给您回复。

[bmarwell]

Kindly re-target against 1.9.x instead. I cannot just change the branch here.

Rationale: detect signature change of public methods.

[bmarwell]

Looks good to me. Will check the checks later and create a 1.10.x branch.

[fpapon]

这是自动回复邮件。你好，您的邮件已经发送到我的邮箱，我看过后会尽快给您回复。

please write in english