Fix bugs reported by users

• Fixed Attribute Error ('ConfigEntries' object has no attribute 'async_setup_platforms' )

Huge update for the users

• Too many changes, too lazy to write them down.
• Summarize: fully re-support 5 EVN companies (cross finger 🤞).

v1.2.9

1. Fixed EVNSPC and EVNNPC updated security.
2. Fixed minor bugs.

v1.2.8

• Fixed datetime display on "Ngày mới nhất" or "Newest Day" sensor

v1.2.7

1. Changed EVN Customer ID requirements.
2. Adjusted ""Newest date" or "Ngày mới nhất" to be more exact.
3. Added support for 3-phase electric lines.
4. Fixed getting old data problems in some areas.
5. Fixed minor bugs.

v1.2.6

1. Fully supported for all EVN branches over Vietnam.
2. Fixed minor bugs.

v1.2.4

• Fixed EVNHANOI data requests (SSL problems).
• Fixed EVNSPC json data.
• Fully supported EVNNPC.

v1.2.3

• Fixed EVNHANOI data requests (SSL problems).
• Fully supported EVNNPC.

v1.2.2

1. Added support for EVNHANOI.
2. Fixed bugs for EVNNPC.
3. Properly displayed errors in config flow.

v1.2.1

Fixes bugs