[Bug] Font style does not apply to year label

[Leon0824]

Version

5.6.0

Link to Minimal Reproduction

https://echarts.apache.org/examples/en/editor.html?c=area-pieces&code=PYBwLglsB2AEC8sDeAoWszGAG0iAXMgL4A0asAHgIIUQDOhq66YAniAKaEDkkAth25lmsAIa06AGVEAjDtkawAZjDAAxUXwjZWPPjGB0QogMaCSy1QGUIALy6wAjAAZYRcqXKsa9RePrScgrIltDqmtq6sNz60IbGZkKhYDb2hC5ubsKwdBwAThAcDLAA2uToTCIY7A7c2BDQ5uXMonkcolZs2A5InlWwACaiYKKEZf3oJdwATM6OAJwAtC7LzkmzzgC62f1TswvLjodJAKwAbFs7VXtzS47Ty9NJAOwnl80iN7OLc8sAzKcABzvCalGbOb4Q5YAFnWb22H2YX2cPz-yxOST-zhBE2RP2hyzOSWh8Kun3BkJOy2emOxCNBeOcZ2WgKSLi2iM2zXc6C5RAA3EA

Steps to Reproduce

Assign font style in this manner to a time-series chart:

xAxis: {
  type: 'time',
  axisLabel: { fontFamily: 'monospace', fontSize: 10 },
},
series: [{ type: 'line', data: [...] }],

Current Behavior

The year label in x-axis is not applied to the assigned font style.

Expected Behavior

The year label in x-axis is applied to the assigned font style.

Environment

Any additional comments?

No response

[helgasoft]

workaround with rich formatting - Demo